UNIT 1: Primitive Types

Overview

AP EXAM WEIGHTING	2.5–5%
CLASS PERIODS	~8–10
OVERVIEW	This unit introduces students to the Java programming language and the use of classes, providing students with a firm foundation of concepts that will be leveraged and built upon in all future units. Students will focus on writing the main method and will start to call preexisting methods to produce output. The use of preexisting methods for input is not prescribed in the course; however, input is a necessary part of any computer science course so teachers will need to determine how they will address this in their classrooms. Students will start to learn about three built-in data types and learn how to create variables, store values, and interact with those variables using basic operations. The ability to write expressions is essential to representing the variability of the real world in a program and will be used in all future units. Primitive data is one of two categories of variables covered in this course. The other category, reference data, will be covered in Unit 2.

1.1 Why Programming? Why Java?

TOPIC	1.1 Why Programming? Why Java?
ENDURING UNDERSTANDING	MOD-1 Some objects or concepts are so frequently represented that programmers can draw upon existing code that has already been tested, enabling them to write solutions more quickly and with a greater degree of confidence.		VAR-1 To find specific solutions to generalizable problems, programmers include variables in their code so that the same algorithm runs using different input values.
LEARNING OBJECTIVE	MOD-1.A Call System class methods to generate output to the console.		VAR-1.A Create string literals
ESSENTIAL KNOWLEDGE	MOD-1.A.1 System.out.print and System.out.println display information on the computer monitor.	MOD-1.A.2 System.out.println moves the cursor to a new line after the information has been displayed, while System.out.print does not.	VAR-1.A.1 A string literal is enclosed in double quotes.

1.2 Variables and Data Types

TOPIC	1.2 Variables and Data Types
ENDURING UNDERSTANDING	VAR-1 To find specific solutions to generalizable problems, programmers include variables in their code so that the same algorithm runs using different input values.
LEARNING OBJECTIVE	VAR-1.B Identify the most appropriate data type category for a particular specification.			VAR-1.C Declare variables of the correct types to represent primitive data.
ESSENTIAL KNOWLEDGE	VAR-1.B.1 A type is a set of values (a domain) and a set of operations on them.	VAR-1.B.2 Data types can be categorized as either primitive or reference.	VAR-1.B.3 The primitive data types used in this course define the set of operations for numbers and Boolean values.	VAR-1.C.1 The three primitive data types used in this course are int, double, and boolean.	VAR-1.C.2 Each variable has associated memory that is used to hold its value.	VAR-1.C.3 The memory associated with a variable of a primitive type holds an actual primitive value	VAR-1.C.4 When a variable is declared final, its value cannot be changed once it is initialized.

1.3 Expressions and Assignment Statements

TOPIC	1.3 Expressions and Assignment Statements
ENDURING UNDERSTANDING	CON-1 The way variables and operators are sequenced and combined in an expression determines the computed result.
LEARNING OBJECTIVE	CON-1.A Evaluate arithmetic expressions in a program code.								CON-1.A.5 An arithmetic operation that uses a double value will evaluate to a double value.
ESSENTIAL KNOWLEDGE	CON-1.A.1 A literal is the source code representation of a fixed value.	CON-1.A.2 Arithmetic expressions include expressions of type int and double.	CON-1.A.3 The arithmetic operators consist of +, −, *, /, and %.	CON-1.A.4 An arithmetic operation that uses two int values will evaluate to an int value.	CON-1.A.5 An arithmetic operation that uses a double value will evaluate to a double value.	CON-1.A.6 Operators can be used to construct compound expressions.	CON-1.A.7 During evaluation, operands are associated with operators according to operator precedence to determine how they are grouped.	CON-1.A.8 An attempt to divide an integer by zero will result in an ArithmeticException to occur.	CON-1.B.1 The assignment operator (=) allows a program to initialize or change the value stored in a variable. The value of the expression on the right is stored in the variable on the left.	CON-1.B.2 During execution, expressions are evaluated to produce a single value	CON-1.B.3 The value of an expression has a type based on the evaluation of the expression.

1.4 Compound Assignment Operators

TOPIC	1.4 Compound Assignment Operators
ENDURING UNDERSTANDING	CON-1 The way variables and operators are sequenced and combined in an expression determines the computed result.
LEARNING OBJECTIVE	CON-1.B Evaluate what is stored in a variable as a result of an expression with an assignment statement.
ESSENTIAL KNOWLEDGE	CON-1.B.4 Compound assignment operators (+=, −=, *=, /=, %=) can be used in place of the assignment operator.	CON-1.B.5 The increment operator (++) and decrement operator (−−) are used to add 1 or subtract 1 from the stored value of a variable or an array element. The new value is assigned to the variable or array element.

1.5 Casting and Ranges of Variables

TOPIC	1.5 Casting and Ranges of Variables
ENDURING UNDERSTANDING	CON-1 The way variables and operators are sequenced and combined in an expression determines the computed result.
LEARNING OBJECTIVE	CON-1.C Evaluate arithmetic expressions that use casting.
ESSENTIAL KNOWLEDGE	CON-1.C.1 The casting operators (int) and (double) can be used to create a temporary value converted to a different data type.	CON-1.C.2 Casting a double value to an int causes the digits to the right of the decimal point to be truncated.	CON-1.C.3 Some programming code causes int values to be automatically cast (widened) to double values.	CON-1.C.4 Values of type double can be rounded to the nearest integer by (int)(x + 0.5) or (int)(x – 0.5) for negative numbers.	CON-1.C.5 Integer values in Java are represented by values of type int, which are stored using a finite amount (4 bytes) of memory. Therefore, an int value must be in the range from Integer.MIN_VALUE to Integer.MAX_VALUE inclusive.	CON-1.C.6 If an expression would evaluate to an int value outside of the allowed range, an integer overflow occurs. This could result in an incorrect value within the allowed range.

Activities

Sample Activities	Error analysis Provide students with code that contains syntax errors. Ask students to identify and correct the errors in the provided code. Once they feel they have identified and corrected all syntax errors, have them verify their conclusion by using a compiler and an IDE that does not autocorrect errors.
	Activating prior knowledge The basic arithmetic operators of +, −, /, and * are similar to what students have experienced in math class or when using a calculator. Give students a list of expressions and ask them to apply what they know from math class to evaluate the meaning of the expressions. Have them verify their results by putting them into a compiler.
	Sharing and responding Put student into groups of two. Provide each student with a different set of statements; in each pair, one student should have a list of statements that contain compound assignment operators, while the other student should have a list of statements that accomplish the same thing without using compound statements. Be sure the statements are in a different order. Students should take turns describing what a statement does to their partner, and the partner should determine which statement of theirs is equivalent to the one being described.
	Predict and compare Provide students with several statements that involve casting. Each cast should be on a different value in the statement. Have students predict the resulting value. For any statements that would not compile or work as intended, have students explain the problem and propose a solution. They should verify their results by putting those results into a compiler.

UNIT 2: Using Objects

Overview

AP EXAM WEIGHTING	5–7.5%
CLASS PERIODS	~13–15
OVERVIEW	In the first unit, students used primitive types to represent real-world data and determined how to use them in arithmetic expressions to solve problems. This unit introduces a new type of data: reference data. Reference data allows real-world objects to be represented in varying degrees specific to a programmer's purpose. This unit builds on students' ability to write expressions by introducing them to Math class methods to write expressions for generating random numbers and other more complex operations. In addition, strings and the existing methods within the String class are an important topic within this unit. Knowing how to declare variables or call methods on objects is necessary throughout the course but will be very important in Units 5 and 9 when teaching students how to write their own classes and about inheritance relationships.

2.1 Objects: Instances of Classes

TOPIC	2.1 Objects: Instances of Classes
ENDURING UNDERSTANDING	MOD-1 Some objects or concepts are so frequently represented that programmers can draw upon existing code that has already been tested, enabling them to write solutions more quickly and with a greater degree of confidence.
LEARNING OBJECTIVE	MOD-1.B Explain the relationship between a class and an object.
ESSENTIAL KNOWLEDGE	MOD-1.B.1 An object is a specific instance of a class with defined attributes.	MOD-1.B.2 A class is the formal implementation, or blueprint, of the attributes and behaviors of an object.

2.2 Creating and Storing Objects (Instantiation)

TOPIC	2.2 Creating and Storing Objects (Instantiation)
ENDURING UNDERSTANDING	MOD-1 Some objects or concepts are so frequently represented that programmers can draw upon existing code that has already been tested, enabling them to write solutions more quickly and with a greater degree of confidence.										VAR-1 To find specific solutions to generalizable problems, programmers include variables in their code so that the same algorithm runs using different input values.
LEARNING OBJECTIVE	MOD-1.C Identify, using its signature, the correct constructor being called.						MOD-1.D For creating objects: a. Create objects by calling constructors without parameters. b. Create objects by calling constructors with parameters.				VAR-1.D Define variables of the correct types to represent reference data.
ESSENTIAL KNOWLEDGE	MOD-1.C.1 A signature consists of the constructor name and the parameter list.	MOD-1.C.2 The parameter list, in the header of a constructor, lists the types of the values that are passed and their variable names. These are often referred to as formal parameters.	MOD-1.C.3 A parameter is a value that is passed into a constructor. These are often referred to as actual parameters.	MOD-1.C.4 Constructors are said to be overloaded when there are multiple constructors with the same name but a different signature.	MOD-1.C.5 The actual parameters passed to a constructor must be compatible with the types identified in the formal parameter list.	MOD-1.C.6 Parameters are passed using call by value. Call by value initializes the formal parameters with copies of the actual parameters.	MOD-1.D For creating objects: a. Create objects by calling constructors without parameters. b. Create objects by calling constructors with parameters.	MOD-1.D.2 A class contains constructors that are invoked to create objects. They have the same name as the class.	MOD-1.D.3 Existing classes and class libraries can be utilized as appropriate to create objects.	MOD-1.D.4 Parameters allow values to be passed to the constructor to establish the initial state of the object.	VAR-1.D.1 The keyword null is a special value used to indicate that a reference is not associated with any object.	VAR-1.D.2 The memory associated with a variable of a reference type holds an object reference value or, if there is no object, null. This value is the memory address of the referenced object.

2.3 Calling a Void Method

TOPIC	2.3 Calling a Void Method
ENDURING UNDERSTANDING	MOD-1 Some objects or concepts are so frequently represented that programmers can draw upon existing code that has already been tested, enabling them to write solutions more quickly and with a greater degree of confidence.
LEARNING OBJECTIVE	MOD-1.E Call non-static void methods without parameters.
ESSENTIAL KNOWLEDGE	MOD-1.E.1 An object’s behavior refers to what the object can do (or what can be done to it) and is defined by methods.	MOD-1.E.2 Procedural abstraction allows a programmer to use a method by knowing what the method does even if they do not know how the method was written.	MOD-1.E.3 A method signature for a method without parameters consists of the method name and an empty parameter list.	MOD-1.E.4 A method or constructor call interrupts the sequential execution of statements, causing the program to first execute the statements in the method or constructor before continuing. Once the last statement in the method or constructor has executed or a return statement is executed, flow of control is returned to the point immediately following where the method or constructor was called.	MOD-1.E.5 Non-static methods are called through objects of the class.	MOD-1.E.6 The dot operator is used along with the object name to call non-static methods.	MOD-1.E.7 Void methods do not have return values and are therefore not called as part of an expression.	MOD-1.E.8 Using a null reference to call a method or access an instance variable causes a NullPointerException to be thrown.

2.4 Calling a Void Method with Parameters

TOPIC	2.4 Calling a Void Method with Parameters
ENDURING UNDERSTANDING	MOD-1 Some objects or concepts are so frequently represented that programmers can draw upon existing code that has already been tested, enabling them to write solutions more quickly and with a greater degree of confidence.
LEARNING OBJECTIVE	MOD-1.F Call non-static void methods with parameters.
ESSENTIAL KNOWLEDGE	MOD-1.F.1 A method signature for a method with parameters consists of the method name and the ordered list of parameter types.	MOD-1.F.2 Values provided in the parameter list need to correspond to the order and type in the method signature.	MOD-1.F.3 Methods are said to be overloaded when there are multiple methods with the same name but a different signature.

2.5 Calling a Non-void Method

TOPIC	2.5 Calling a Non-void Method
ENDURING UNDERSTANDING	MOD-1 Some objects or concepts are so frequently represented that programmers can draw upon existing code that has already been tested, enabling them to write solutions more quickly and with a greater degree of confidence.
LEARNING OBJECTIVE	MOD-1.G Call non-static non-void methods with or without parameters.
ESSENTIAL KNOWLEDGE	MOD-1.G.1 Non-void methods return a value that is the same type as the return type in the signature. To use the return value when calling a non-void method, it must be stored in a variable or used as part of an expression.

2.6 String Objects: Concatenation, Literals, and More

TOPIC	2.6 String Objects: Concatenation, Literals, and More
ENDURING UNDERSTANDING	VAR-1 To find specific solutions to generalizable problems, programmers include variables in their code so that the same algorithm runs using different input values.
LEARNING OBJECTIVE	VAR-1.E For String class: a. Create String objects. b. Call String methods.
ESSENTIAL KNOWLEDGE	VAR-1.E.1 String objects can be created by using string literals or by calling the String class constructor	VAR-1.E.2 String objects are immutable, meaning that String methods do not change the String object.	VAR-1.E.3 String objects can be concatenated using the + or += operator, resulting in a new String object.	VAR-1.E.4 Primitive values can be concatenated with a String object. This causes implicit conversion of the values to String objects.	VAR-1.E.5 Escape sequences start with a \ and have a special meaning in Java. Escape sequences used in this course include \”, \\, and \n.

2.7 String Methods

TOPIC	2.7 String Methods
ENDURING UNDERSTANDING	VAR-1 To find specific solutions to generalizable problems, programmers include variables in their code so that the same algorithm runs using different input values.
LEARNING OBJECTIVE	VAR-1.E For String class: a. Create String objects. b. Call String methods.
ESSENTIAL KNOWLEDGE	VAR-1.E.6 Application program interfaces (APIs) and libraries simplify complex programming tasks.	VAR-1.E.7 Documentation for APIs and libraries are essential to understanding the attributes and behaviors of an object of a class.	VAR-1.E.8 Classes in the APIs and libraries are grouped into packages.	VAR-1.E.9 The String class is part of the java.lang package. Classes in the java.lang package are available by default.	VAR-1.E.10 A String object has index values from 0 to length – 1. Attempting to access indices outside this range will result in an IndexOutOfBoundsException.	VAR-1.E.11 A String object can be concatenated with an object reference, which implicitly calls the referenced object’s toString method.	VAR-1.E.12 The following String methods and constructors—including what they do and when they are used—are part of the Java Quick Reference: § String(String str) — Constructs a new String object that represents the same sequence of characters as str § int length() — Returns the number of characters in a String object § String substring (int from, int to) returns stubstring starting at from ending at to -1 § String substring(int from) — Returns substring(from, length()) § int indexOf(String str) — Returns the index of the first occurrence of str; returns -1 if not found § boolean equals(String other) — Returns true if this is equal to other; returns false otherwise § int compareTo(String other) — Returns a value < 0 if this is less than other; returns zero if this is equal to other; returns a value > 0 if this is greater than other	VAR-1.E.13 A string identical to the single element substring at position index can be created by calling substring(index, index + 1)

Activities

Sample Activities	Using manipulatives When introducing students to the idea of creating objects, you can use a cookie cutter and modeling clay or dough, with the cutter representing the class and the cut dough representing the objects. For each object cut, write the instantiation. Ask students to describe what the code is doing and how the different parameter values (e.g., thickness, color) change the object that was created.
	Marking the text Provide students with several statements that define a variable and create an object on a single line. Have students mark up the statements by circling the assignment operator and the new keyword. Then, have students underline the variable type and the constructor. Lastly, have them draw a rectangle around the list of actual parameters being passed to the constructor. Using these marked-up statements, ask students to create several new variables and objects.
	Think-pair-share Provide students with several code segments, each with a missing expression that would contain a call to a method in the Math class, and a description of the intended outcome of each code segment. Ask them which statement should be used to complete the code segment. Have them share their responses with a partner to compare answers and come to agreement, and then have groups share with the entire class.

UNIT 3: Boolean Expressions and if Statements

Overview

AP EXAM WEIGHTING	15–17.5%
CLASS PERIODS	~11–13
OVERVIEW	Algorithms are composed of three building blocks: sequencing, selection, and iteration. This unit focuses on selection, which is represented in a program by using conditional statements. Conditional statements give the program the ability to decide and respond appropriately and are a critical aspect of any nontrivial computer program. In addition to learning the syntax and proper use of conditional statements, students will build on the introduction of Boolean variables by writing Boolean expressions with relational and logical operators. The third building block of all algorithms is iteration, which you will cover in Unit 4. Selection and iteration work together to solve problems.

3.1 Boolean Expressions

TOPIC	3.1 Boolean Expressions
ENDURING UNDERSTANDING	CON-1 The way variables and operators are sequenced and combined in an expression determines the computed result.
LEARNING OBJECTIVE	CON-1.E Evaluate Boolean expressions that use relational operators in program code.
ESSENTIAL KNOWLEDGE	CON-1.E.1 Primitive values and reference values can be compared using relational operators (i.e., == and !=).	CON-1.E.2 Arithmetic expression values can be compared using relational operators (i.e., <, >, <=, >=).	CON-1.E.3 An expression involving relational operators evaluates to a Boolean value.

3.2 if Statements and Control Flow

TOPIC	3.2 if Statements and Control Flow
ENDURING UNDERSTANDING	CON-2 Programmers incorporate iteration and selection into code as a way of providing instructions for the computer to process each of the many possible input values.
LEARNING OBJECTIVE	CON-2.A Represent branching logical processes by using conditional statements.
ESSENTIAL KNOWLEDGE	CON-2.A.1 Conditional statements interrupt the sequential execution of statements.	CON-2.A.2 if statements affect the flow of control by executing different statements based on the value of a Boolean expression.	CON-2.A.3 A one-way selection (if statement) is written when there is a set of statements to execute under a certain condition. In this case, the body is executed only when the Boolean condition is true.

3.3 if-else Statements

TOPIC	3.3 if-else Statements
ENDURING UNDERSTANDING	CON-2 Programmers incorporate iteration and selection into code as a way of providing instructions for the computer to process each of the many possible input values.
LEARNING OBJECTIVE	CON-2.A Represent branching logical processes by using conditional statements.
ESSENTIAL KNOWLEDGE	CON-2.A.4 A two-way selection is written when there are two sets of statements— one to be executed when the Boolean condition is true, and another set for when the Boolean condition is false. In this case, the body of the “if” is executed when the Boolean condition is true, and the body of the “else” is executed when the Boolean condition is false.

3.4 else if Statements

TOPIC	3.4 else if Statements
ENDURING UNDERSTANDING	CON-2 Programmers incorporate iteration and selection into code as a way of providing instructions for the computer to process each of the many possible input values.
LEARNING OBJECTIVE	CON-2.A Represent branching logical processes by using conditional statements.
ESSENTIAL KNOWLEDGE	CON-2.A.5 A multi-way selection is written when there are a series of conditions with different statements for each condition. Multi-way selection is performed using if-else-if statements such that exactly one section of code is executed based on the first condition that evaluates to true.

3.5 Compound Boolean Expressions

TOPIC	3.5 Compound Boolean Expressions
ENDURING UNDERSTANDING	CON-2 Programmers incorporate iteration and selection into code as a way of providing instructions for the computer to process each of the many possible input values.	CON-1 The way variables and operators are sequenced and combined in an expression determines the computed result.
LEARNING OBJECTIVE	CON-2.B Represent branching logical processes by using nested conditional statements.	CON-1.F Evaluate compound Boolean expressions in program code.
ESSENTIAL KNOWLEDGE	CON-2.B.1 Nested if statements consist of if statements within if statements.	CON-1.F.1 Logical operators !(not), &&(and), and ||(or) are used with Boolean values. This represents the order these operators will be evaluated.	CON-1.F.2 An expression involving logical operators evaluates to a Boolean value.	CON-1.F.3 When the result of a logical expression using && or || can be determined by evaluating only the first Boolean operand, the second is not evaluated. This is known as short-circuited evaluation.

3.6 Equivalent Boolean Expressions

TOPIC	3.6 Equivalent Boolean Expressions
ENDURING UNDERSTANDING	CON-1 The way variables and operators are sequenced and combined in an expression determines the computed result.
LEARNING OBJECTIVE	CON-1.G Compare and contrast equivalent Boolean expressions.
ESSENTIAL KNOWLEDGE	CON-1.G.1 De Morgan’s Laws can be applied to Boolean expressions.	CON-1.G.2 Truth tables can be used to prove Boolean identities.	CON-1.G.3 Equivalent Boolean expressions will evaluate to the same value in all cases.

3.7 Comparing Objects

TOPIC	3.7 Comparing Objects
ENDURING UNDERSTANDING	CON-1 The way variables and operators are sequenced and combined in an expression determines the computed result.
LEARNING OBJECTIVE	CON-1.H Compare object references using Boolean expressions in program code.
ESSENTIAL KNOWLEDGE	CON-1.H.1 Two object references are considered aliases when they both reference the same object.	CON-1.H.2 Object reference values can be compared, using == and !=, to identify aliases.	CON-1.H.3 A reference value can be compared with null, using == or !=, to determine if the reference actually references an object.	CON-1.H.4 Often classes have their own equals method, which can be used to determine whether two objects of the class are equivalent.

Activities

Sample Activities	Code tracing Provide students with several code segments that contain conditional statements. Have students trace various sample inputs, keeping track of the statements that get executed and the order in which they are executed. This can help students find errors and validate results.
	Pair programming Have students work with a partner to create a “guess checker” that could be used as part of a larger game. Students compare four given digits to a preexisting four-digit code that is stored in individual variables. Their program should provide output containing the number of correct digits in correct locations, as well as the number of correct digits in incorrect locations. This program can be continually improved as students learn about nested conditional statements and compound Boolean expressions.
	Diagramming Have students create truth tables by listing all the possible true and false combinations and corresponding Boolean values for a given compound Boolean expression. Once students have created the truth table, provide students with input values. Have students determine the value of each individual Boolean expression and use the truth table to determine the result of the compound Boolean expression.
	Student response system Provide students with a code segment that utilizes conditional statements and a compound Boolean expression, and ask them to choose an equivalent code segment that uses a nested conditional statement (and vice versa). Have them report their responses using a student response system.
	Predict and compare Have students predict the output of several different code segments that compare object references—some that use .equals() and some that use ==. Once done, have them create a program that contains those code segments and compare the actual and expected results. This is best illustrated using a simple class that you write yourself.

UNIT 4: Iteration

Overview

AP EXAM WEIGHTING	17.5–22.5%
CLASS PERIODS	~14–16
OVERVIEW	This unit focuses on iteration using while and for loops. As you saw in Unit 3, Boolean expressions are useful when a program needs to perform different operations under different conditions. Boolean expressions are also one of the main components in iteration. This unit introduces several standard algorithms that use iteration. Knowledge of standard algorithms makes solving similar problems easier, as algorithms can be modified or combined to suit new situations. Iteration is used when traversing data structures such as arrays, ArrayLists, and 2D arrays. In addition, it is a necessary component of several standard algorithms, including searching and sorting, which will be covered in later units.

4.1 while Loops

TOPIC	4.1 while Loops
ENDURING UNDERSTANDING	CON-2 Programmers incorporate iteration and selection into code as a way of providing instructions for the computer to process each of the many possible input values.
LEARNING OBJECTIVE	CON-2.C Represent iterative processes using a while loop.					CON-2.D For algorithms in the context of a particular specification that does not require the use of traversals: § Identify standard algorithms. § Modify standard algorithms. § Develop an algorithm.
ESSENTIAL KNOWLEDGE	CON-2.C.1 Iteration statements change the flow of control by repeating a set of statements zero or more times until a condition is met.	CON-2.C.2 In loops, the Boolean expression is evaluated before each iteration of the loop body, including the first. When the expression evaluates to true, the loop body is executed. This continues until the expression evaluates to false, whereupon the iteration ceases.	CON-2.C.3 A loop is an infinite loop when the Boolean expression always evaluates to true.	CON-2.C.4 If the Boolean expression evaluates to false initially, the loop body is not executed at all.	CON-2.C.5 Executing a return statement inside an iteration statement will halt the loop and exit the method or constructor.	CON-2.D.1 There are standard algorithms to: § Identify if an integer is or is not evenly divisible by another integer § Identify the individual digits in an integer § Determine the frequency with which a specific criterion is met	CON-2.D.2 There are standard algorithms to: § Determine a minimum or maximum value § Compute a sum, average, or mode

4.2 for Loops

TOPIC	4.2 for Loops
ENDURING UNDERSTANDING	CON-2 Programmers incorporate iteration and selection into code as a way of providing instructions for the computer to process each of the many possible input values.
LEARNING OBJECTIVE	CON-2.E Represent iterative processes using a for loop.
ESSENTIAL KNOWLEDGE	CON-2.E.1 There are three parts in a for loop header: the initialization, the Boolean expression, and the increment. The increment statement can also be a decrement statement.	CON-2.E.2 In a for loop, the initialization statement is only executed once before the first Boolean expression evaluation. The variable being initialized is referred to as a loop control variable.	CON-2.E.3 In each iteration of a for loop, the increment statement is executed after the entire loop body is executed and before the Boolean expression is evaluated again.	CON-2.E.4 A for loop can be rewritten into an equivalent while loop and vice versa.	CON-2.E.5 “Off by one” errors occur when the iteration statement loops one time too many or one time too few.

4.3 Developing Algorithms Using Strings

TOPIC	4.3 Developing Algorithms Using Strings
ENDURING UNDERSTANDING	CON-2 Programmers incorporate iteration and selection into code as a way of providing instructions for the computer to process each of the many possible input values.
LEARNING OBJECTIVE	CON-2.F For algorithms in the context of a particular specification that involves String objects: § Identify standard algorithms. § Modify standard algorithms. § Develop an algorithm.
ESSENTIAL KNOWLEDGE	CON-2.F.1 There are standard algorithms that utilize String traversals to: § Find if one or more substrings has a particular property § Determine the number of substrings that meet specific criteria § Create a new string with the characters reversed

4.4 Nested Iteration

TOPIC	4.4 Nested Iteration
ENDURING UNDERSTANDING	CON-2 Programmers incorporate iteration and selection into code as a way of providing instructions for the computer to process each of the many possible input values.
LEARNING OBJECTIVE	CON-2.G Represent nested iterative processes.
ESSENTIAL KNOWLEDGE	CON-2.G.1 Nested iteration statements are iteration statements that appear in the body of another iteration statement.	CON-2.G.2 When a loop is nested inside another loop, the inner loop must complete all its iterations before the outer loop can continue.

4.5 Informal Code Analysis

TOPIC	4.5 Informal Code Analysis
ENDURING UNDERSTANDING	CON-2 Programmers incorporate iteration and selection into code as a way of providing instructions for the computer to process each of the many possible input values.
LEARNING OBJECTIVE	CON-2.H Compute statement execution counts and informal run-time comparison of iterative statements.
ESSENTIAL KNOWLEDGE	CON-2.H.1 A statement execution count indicates the number of times a statement is executed by the program.

Activities

Sample Activities	Jigsaw As a whole class, look at a code segment containing iteration and the resulting output. Afterward, divide students into groups, and provide each group with a slightly modified code segment. After groups have determined how the result changes based on their modified segment, have them get together with students who investigated a different version of the code segment and share their conclusions.
	Note-taking Provide students with a method that, when given an integer, returns the month name from a String that includes all the month names in order, each separated by a space. Have them annotate what each statement does in the method. Then, ask students to use their annotated method as a guide to write a similar method that, given a student number as input, returns the name of a student from a String containing the first name of all students in the class, each separated by a space.
	Simplify the problem Provide students with several code segments containing iteration. For each segment, have students trace through the execution of a loop with smaller bounds to see what boundary cases are considered, and then use that information to determine the number of times each loop executes with the original bounds.

UNIT 5: Writing Classes

AP EXAM WEIGHTING	5–7.5%
CLASS PERIODS	~12–14
OVERVIEW	This unit will pull together information from all previous units to create new, user-defined reference data types in the form of classes. The ability to accurately model real-world entities in a computer program is a large part of what makes computer science so powerful. This unit focuses on identifying appropriate behaviors and attributes of real-world entities and organizing these into classes. Students will build on what they learn in this unit to represent relationships between classes through hierarchies, which appear in Unit 9. The creation of computer programs can have extensive impacts on societies, economies, and cultures. The legal and ethical concerns that come with programs and the responsibilities of programmers are also addressed in this unit.

5.1 Anatomy of a Class

TOPIC	5.1 Anatomy of a Class
ENDURING UNDERSTANDING	MOD-2 Programmers use code to represent a physical object or nonphysical concept, real or imagined, by defining a class based on the attributes and/or behaviors of the object or concept.						MOD-3 When multiple classes contain common attributes and behaviors, programmers create a new class containing the shared attributes and behaviors forming a hierarchy. Modifications made at the highest level of the hierarchy apply to the subclasses.
LEARNING OBJECTIVE	MOD-2.A Designate access and visibility constraints to classes, data, constructors, and methods.						MOD-3.A Designate private visibility of instance variables to encapsulate the attributes of an object.
ESSENTIAL KNOWLEDGE	MOD-2.A.1 The keywords public and private affect the access of classes, data, constructors, and methods.	MOD-2.A.2 The keyword private restricts access to the declaring class, while the keyword public allows access from classes outside the declaring class.	MOD-2.A.3 Classes are designated public.	MOD-2.A.4 Access to attributes should be kept internal to the class. Therefore, instance variables are designated as private.	MOD-2.A.5 Constructors are designated public.	MOD-2.A.6 Access to behaviors can be internal or external to the class. Therefore, methods can be designated as either public or private.	MOD-3.A.1 Data encapsulation is a technique in which the implementation details of a class are kept hidden from the user.	MOD-3.A.2 When designing a class, programmers make decisions about what data to make accessible and modifiable from an external class. Data can be either accessible or modifiable, or it can be both or neither.	MOD-3.A.3 Instance variables are encapsulated by using the private access modifier.	MOD-3.A.4 The provided accessor and mutator methods in a class allow client code to use and modify data.

5.2 Constructors

TOPIC	5.2 Constructors
ENDURING UNDERSTANDING	MOD-2 Programmers use code to represent a physical object or nonphysical concept, real or imagined, by defining a class based on the attributes and/or behaviors of the object or concept.
LEARNING OBJECTIVE	MOD-2.B Define instance variables for the attributes to be initialized through the constructors of a class.
ESSENTIAL KNOWLEDGE	MOD-2.B.1 An object’s state refers to its attributes and their values at a given time and is defined by instance variables belonging to the object. This creates a “has-a” relationship between the object and its instance variables.	MOD-2.B.2 Constructors are used to set the initial state of an object, which should include initial values for all instance variables.	MOD-2.B.3 Constructor parameters are local variables to the constructor and provide data to initialize instance variables.	MOD-2.B.4 When a mutable object is a constructor parameter, the instance variable should be initialized with a copy of the referenced object. In this way, the instance variable is not an alias of the original object, and methods are prevented from modifying the state of the original object.	MOD-2.B.5 When no constructor is written, Java provides a no-argument constructor, and the instance variables are set to default values.

5.3 Documentation with Comments

TOPIC	5.3 Documentation with Comments
ENDURING UNDERSTANDING	MOD-2 Programmers use code to represent a physical object or nonphysical concept, real or imagined, by defining a class based on the attributes and/or behaviors of the object or concept.
LEARNING OBJECTIVE	MOD-2.C Describe the functionality and use of program code through comments.
ESSENTIAL KNOWLEDGE	MOD-2.C.1 Comments are ignored by the compiler and are not executed when the program is run.	MOD-2.C.2 Three types of comments in Java include /* */, which generates a block of comments, //, which generates a comment on one line, and /** */, which are Javadoc comments and are used to create API documentation.	MOD-2.C.3 A precondition is a condition that must be true just prior to the execution of a section of program code in order for the method to behave as expected. There is no expectation that the method will check to ensure preconditions are satisfied.	MOD-2.C.4 A postcondition is a condition that must always be true after the execution of a section of program code. Postconditions describe the outcome of the execution in terms of what is being returned or the state of an object.	MOD-2.C.5 Programmers write method code to satisfy the postconditions when preconditions are met.

5.4 Accessor Methods

TOPIC	5.4 Accessor Methods
ENDURING UNDERSTANDING	MOD-2 Programmers use code to represent a physical object or nonphysical concept, real or imagined, by defining a class based on the attributes and/or behaviors of the object or concept.
LEARNING OBJECTIVE	MOD-2.D Define behaviors of an object through non-void methods without parameters written in a class.
ESSENTIAL KNOWLEDGE	MOD-2.D.1 An accessor method allows other objects to obtain the value of instance variables or static variables.	MOD-2.D.2 A non-void method returns a single value. Its header includes the return type in place of the keyword void.	MOD-2.D.3 In non-void methods, a return expression compatible with the return type is evaluated, and a copy of that value is returned. This is referred to as “return by value.”	MOD-2.D.4 When the return expression is a reference to an object, a copy of that reference is returned, not a copy of the object.	MOD-2.D.5 The return keyword is used to return the flow of control to the point immediately following where the method or constructor was called.	MOD-2.D.6 The toString method is an overridden method that is included in classes to provide a description of a specific object. It generally includes what values are stored in the instance data of the object.	MOD-2.D.7 If System.out.print or System.out. println is passed an object, that object’s toString method is called, and the returned string is printed.

5.5 Mutator Methods

TOPIC	5.5 Mutator Methods
ENDURING UNDERSTANDING	MOD-2 Programmers use code to represent a physical object or nonphysical concept, real or imagined, by defining a class based on the attributes and/or behaviors of the object or concept.
LEARNING OBJECTIVE	MOD-2.E Define behaviors of an object through void methods with or without parameters written in a class.
ESSENTIAL KNOWLEDGE	MOD-2.E.1 A void method does not return a value. Its header contains the keyword void before the method name.	MOD-2.E.2 A mutator (modifier) method is often a void method that changes the values of instance variables or static variables.

5.6 Writing Methods

TOPIC	5.6 Writing Methods
ENDURING UNDERSTANDING	MOD-2 Programmers use code to represent a physical object or nonphysical concept, real or imagined, by defining a class based on the attributes and/or behaviors of the object or concept.
LEARNING OBJECTIVE	MOD-2.F Define behaviors of an object through non-void methods with parameters written in a class.
ESSENTIAL KNOWLEDGE	MOD-2.F.1 Methods can only access the private data and methods of a parameter that is a reference to an object when the parameter is the same type as the method’s enclosing class.	MOD-2.F.2 Non-void methods with parameters receive values through parameters, use those values, and return a computed value of the specified type.	MOD-2.F.3 It is good programming practice to not modify mutable objects that are passed as parameters unless required in the specification.	MOD-2.F.4 When an actual parameter is a primitive value, the formal parameter is initialized with a copy of that value. Changes to the formal parameter have no effect on the corresponding actual parameter.	MOD-2.F.5 When an actual parameter is a reference to an object, the formal parameter is initialized with a copy of that reference, not a copy of the object. If the reference is to a mutable object, the method or constructor can use this reference to alter the state of the object.	MOD-2.F.6 Passing a reference parameter results in the formal parameter and the actual parameter being aliases. They both refer to the same object.

5.7 Static Variables and Methods

TOPIC	5.7 Static Variables and Methods
ENDURING UNDERSTANDING	MOD-2 Programmers use code to represent a physical object or nonphysical concept, real or imagined, by defining a class based on the attributes and/or behaviors of the object or concept.
LEARNING OBJECTIVE	MOD-2.G Define behaviors of a class through static methods.					MOD-2.H Define the static variables that belong to the class.
ESSENTIAL KNOWLEDGE	MOD-2.G.1 Static methods are associated with the class, not objects of the class.	MOD-2.G.2 Static methods include the keyword static in the header before the method name.	MOD-2.G.3 Static methods cannot access or change the values of instance variables.	MOD-2.G.4 Static methods can access or change the values of static variables.	MOD-2.G.5 Static methods do not have a this reference and are unable to use the class’s instance variables or call non-static methods.	MOD-2.H.1 Static variables belong to the class, with all objects of a class sharing a single static variable.	MOD-2.H.2 Static variables can be designated as either public or private and are designated with the static keyword before the variable type.	MOD-2.H.3 Static variables are used with the class name and the dot operator, since they are associated with a class, not objects of a class.

5.8 Scope and Access

TOPIC	5.8 Scope and Access
ENDURING UNDERSTANDING	VAR-1 To find specific solutions to generalizable problems, programmers include variables in their code so that the same algorithm runs using different input values.
LEARNING OBJECTIVE	VAR-1.G Explain where variables can be used in the program code.
ESSENTIAL KNOWLEDGE	VAR-1.G.1 Local variables can be declared in the body of constructors and methods. These variables may only be used within the constructor or method and cannot be declared to be public or private.	VAR-1.G.2 When there is a local variable with the same name as an instance variable, the variable name will refer to the local variable instead of the instance variable.	VAR-1.G.3 Formal parameters and variables declared in a method or constructor can only be used within that method or constructor.	VAR-1.G.4 Through method decomposition, a programmer breaks down a large problem into smaller subproblems by creating methods to solve each individual subproblem.

5.9 this Keyword

TOPIC	5.9 this Keyword
ENDURING UNDERSTANDING	VAR-1 To find specific solutions to generalizable problems, programmers include variables in their code so that the same algorithm runs using different input values.
LEARNING OBJECTIVE	VAR-1.H Evaluate object reference expressions that use the keyword this.
ESSENTIAL KNOWLEDGE	VAR-1.H.1 Within a non-static method or a constructor, the keyword this is a reference to the current object—the object whose method or constructor is being called.	VAR-1.H.2 The keyword this can be used to pass the current object as an actual parameter in a method call.

5.10 Ethical and Social Implications of Computing Systems

TOPIC	5.10 Ethical and Social Implications of Computing Systems
ENDURING UNDERSTANDING	IOC-1 While programs are typically designed to achieve a specific purpose, they may have unintended consequences.
LEARNING OBJECTIVE	IOC-1.A Explain the ethical and social implications of computing systems.
ESSENTIAL KNOWLEDGE	IOC-1.A.1 System reliability is limited. Programmers should make an effort to maximize system reliability.	IOC-1.A.2 Legal issues and intellectual property concerns arise when creating programs.	IOC-1.A.3 The creation of programs has impacts on society, economies, and culture. These impacts can be beneficial and/or harmful.

Activities

Sample Activities	Kinesthetic learning Have students break into groups of 4–5 to play board games. Ask them to play the game for about 10 minutes. While they play the game, they should keep track of the various nouns they encounter and actions that happen as part of the game. The nouns can be represented in the computer as classes, and the actions are the behaviors. At the end of game play, ask students to create UML diagrams for the identified classes.
	Marking the text Present students with specifications, and have them highlight or underline any preconditions (both implicit and explicit) that exist for the method to function. This includes information about parameters, such as object references not being null.
	Create a plan When asked to write a method, have students write an outline using pseudocode with paper and pencil. Then, go through it step-by-step with sample input to ensure that the process is correct and to determine if any additional information is needed before beginning to program a solution on the computer.
	Paraphrase Provide students with several example classes that utilize static variables for unique identification numbers or for counting the number of objects that have been created, but do not provide any description or documentation for the code. Have students spend time creating objects and calling the static methods to investigate how the static variables behave, then have them document the code appropriately to describe how each class utilizes static variables and methods.

UNIT 6: Array

Overview

AP EXAM WEIGHTING	10–15%
CLASS PERIODS	~6–8
OVERVIEW	This unit focuses on data structures, which are used to represent collections of related data using a single variable rather than multiple variables. Using a data structure along with iterative statements with appropriate bounds will allow for similar treatment to be applied more easily to all values in the collection. Just as there are useful standard algorithms when dealing with primitive data, there are standard algorithms to use with data structures. In this unit, we apply standard algorithms to arrays; however, these same algorithms are used with ArrayLists and 2D arrays as well. Additional standard algorithms, such as standard searching and sorting algorithms, will be covered in the next unit.

6.1 Array Creation and Access

TOPIC	6.1 Array Creation and Access
ENDURING UNDERSTANDING	VAR-2 To manage large amounts of data or complex relationships in data, programmers write code that groups the data together into a single data structure without creating individual variables for each value.
LEARNING OBJECTIVE	VAR-2.A Represent collections of related primitive or object reference data using onedimensional (1D) array objects.
ESSENTIAL KNOWLEDGE	VAR-2.A.1 The use of array objects allows multiple related items to be represented using a single variable.	VAR-2.A.2 The size of an array is established at the time of creation and cannot be changed.	VAR-2.A.3 Arrays can store either primitive data or object reference data.	VAR-2.A.4 When an array is created using the keyword new, all of its elements are initialized with a specific value based on the type of elements: § Elements of type int are initialized to 0 § Elements of type double are initialized to 0.0 § Elements of type boolean are initialized to false § Elements of a reference type are initialized to the reference value null. No objects are automatically created	VAR-2.A.5 Initializer lists can be used to create and initialize arrays.	VAR-2.A.6 Square brackets ([ ]) are used to access and modify an element in a 1D array using an index.	VAR-2.A.7 The valid index values for an array are 0 through one less than the number of elements in the array, inclusive. Using an index value outside of this range will result in an ArrayIndexOutOfBoundsException being thrown.

6.2 Traversing Arrays

TOPIC	6.2 Traversing Arrays
ENDURING UNDERSTANDING	VAR-2 To manage large amounts of data or complex relationships in data, programmers write code that groups the data together into a single data structure without creating individual variables for each value.
LEARNING OBJECTIVE	VAR-2.B Traverse the elements in a 1D array
ESSENTIAL KNOWLEDGE	VAR-2.B.1 Iteration statements can be used to access all the elements in an array. This is called traversing the array	VAR-2.B.2 Traversing an array with an indexed for loop or while loop requires elements to be accessed using their indices.	VAR-2.B.3 Since the indices for an array start at 0 and end at the number of elements − 1, “off by one” errors are easy to make when traversing an array, resulting in an ArrayIndexOutOfBoundsException being thrown.

6.3 Enhanced for Loop for Arrays

TOPIC	6.3 Enhanced for Loop for Arrays
ENDURING UNDERSTANDING	VAR-2 To manage large amounts of data or complex relationships in data, programmers write code that groups the data together into a single data structure without creating individual variables for each value.
LEARNING OBJECTIVE	VAR-2.C Traverse the elements in a 1D array object using an enhanced for loop.
ESSENTIAL KNOWLEDGE	VAR-2.C.1 An enhanced for loop header includes a variable, referred to as the enhanced for loop variable.	VAR-2.C.2 For each iteration of the enhanced for loop, the enhanced for loop variable is assigned a copy of an element without using its index.	VAR-2.C.3 Assigning a new value to the enhanced for loop variable does not change the value stored in the array.	VAR-2.C.4 Program code written using an enhanced for loop to traverse and access elements in an array can be rewritten using an indexed for loop or a while loop.

6.4 Developing Algorithms Using Arrays

TOPIC	6.4 Developing Algorithms Using Arrays
ENDURING UNDERSTANDING	CON-2 Programmers incorporate iteration and selection into code as a way of providing instructions for the computer to process each of the many possible input values.
LEARNING OBJECTIVE	CON-2.I For algorithms in the context of a particular specification that requires the use of array traversals: § Identify standard algorithms. § Modify standard algorithms. § Develop an algorithm.
ESSENTIAL KNOWLEDGE	CON-2.I.1 There are standard algorithms that utilize array traversals to: § Determine a minimum or maximum value § Compute a sum, average, or mode § Determine if at least one element has a particular property § Determine if all elements have a particular property § Access all consecutive pairs of elements § Determine the presence or absence of duplicate elements § Determine the number of elements meeting specific criteria	CON-2.I.2 There are standard array algorithms that utilize traversals to: § Shift or rotate elements left or right § Reverse the order of the elements

Activities

Sample Activities	Diagramming Provide students with several prompts to create and access elements in an array. After they have determined the code for each prompt, have students draw a memory diagram that shows references and the arrays they point to. Have students update the diagram with each statement to demonstrate how changing the contents through one array reference effects all the array references for this array.
	Error analysis Provide students with several error-ridden code segments containing array traversals along with the expected output of each segment. Ask them to identify any errors that they see on paper and to suggest fixes to provide the expected output. Have them type up their solutions in an IDE to verify their work.
	Think-pair-share Ask students to consider two program code segments that are meant to yield the same result: one using a traditional for loop and one using a for each loop. Have them take a few minutes to think independently about whether the two segments accomplish the same result and, if not, what changes could be made in order for that to happen. Then, ask students to work with their partners to come up with situations where it would make sense to use one type of loop over the other before sharing with the whole class.
	Pair programming Have students use pair programming to solve an array-based free-response question. Have one student be the driver for Part A while the other navigates, then have them switch for Part B. Once they are done, have partners switch solutions with another group and work through the scoring guidelines to “grade” that solution. Spend time as a class discussing the different approaches students used.

UNIT 7: ArrayList

Overview

AP EXAM WEIGHTING	2.5–7.5%
CLASS PERIODS	~10–12
OVERVIEW	As students learned in Unit 6, data structures are helpful when storing multiple related data values. Arrays have a static size, which causes limitations related to the number of elements stored, and it can be challenging to reorder elements stored in arrays. The ArrayList object has a dynamic size, and the class contains methods for insertion and deletion of elements, making reordering and shifting items easier. Deciding which data structure to select becomes increasingly important as the size of the data set grows, such as when using a large real-world data set. In this unit, students will also learn about privacy concerns related to storing large amounts of personal data and about what can happen if such information is compromised.

7.1 Introduction to ArrayList

TOPIC	7.1 Introduction to ArrayList
ENDURING UNDERSTANDING	VAR-2 To manage large amounts of data or complex relationships in data, programmers write code that groups the data together into a single data structure without creating individual variables for each value.
LEARNING OBJECTIVE	VAR-2.D Represent collections of related object reference data using ArrayList objects.
ESSENTIAL KNOWLEDGE	VAR-2.D.1 An ArrayList object is mutable and contains object references.	VAR-2.D.2 The ArrayList constructor ArrayList() constructs an empty list.	VAR-2.D.3 Java allows the generic type ArrayList<E>, where the generic type E specifies the type of the elements.	VAR-2.D.4 When ArrayList<E> is specified, the types of the reference parameters and return type when using the methods are type E.	VAR-2.D.5 ArrayList<E> is preferred over ArrayList because it allows the compiler to find errors that would otherwise be found at run-time.

7.2 ArrayList Methods

TOPIC	7.2 ArrayList Methods
ENDURING UNDERSTANDING	VAR-2 To manage large amounts of data or complex relationships in data, programmers write code that groups the data together into a single data structure without creating individual variables for each value.
LEARNING OBJECTIVE	VAR-2.D Represent collections of related object reference data using ArrayList objects.
ESSENTIAL KNOWLEDGE	VAR-2.D.6 The ArrayList class is part of the java. util package. An import statement can be used to make this class available for use in the program.	VAR-2.D.7 The following ArrayList methods— including what they do and when they are used—are part of the Java Quick Reference: § int size() - Returns the number of elements in the list § boolean add(E obj) - Appends obj to end of list; returns true § void add(int index, E obj) - Inserts obj at position index (0 <= index <= size), moving elements at position index and higher to the right (adds 1 to their indices) and adds 1 to size § E get(int index) - Returns the element at position index in the list § E set(int index, E obj) — Replaces the element at position index with obj;returns the element formerly at position index § E remove(int index) — Removes element from position index, moving elements at position index + 1 and higher to the left (subtracts 1 from their indices) and subtracts 1 from size; returns the element formerly at position index

7.3 Traversing ArrayLists

TOPIC	7.3 Traversing ArrayLists
ENDURING UNDERSTANDING	VAR-2 To manage large amounts of data or complex relationships in data, programmers write code that groups the data together into a single data structure without creating individual variables for each value.
LEARNING OBJECTIVE	VAR-2.E For ArrayList objects: a. Traverse using a for or while loop b. Traverse using an enhanced for loop
ESSENTIAL KNOWLEDGE	VAR-2.E.1 Iteration statements can be used to access all the elements in an ArrayList. This is called traversing the ArrayList.	VAR-2.E.2 Deleting elements during a traversal of an ArrayList requires using special techniques to avoid skipping elements.	VAR-2.E.3 Since the indices for an ArrayList start at 0 and end at the number of elements − 1, accessing an index value outside of this range will result in an ArrayIndexOutOfBoundsException being thrown.	VAR-2.E.4 Changing the size of an ArrayList while traversing it using an enhanced for loop can result in a ConcurrentModificationException being thrown. Therefore, when using an enhanced for loop to traverse an ArrayList, you should not add or remove elements.

7.4 Developing Algorithms Using ArrayLists

TOPIC	7.4 Developing Algorithms Using ArrayLists
ENDURING UNDERSTANDING	CON-2 Programmers incorporate iteration and selection into code as a way of providing instructions for the computer to process each of the many possible input values.
LEARNING OBJECTIVE	CON-2.J For algorithms in the context of a particular specification that requires the use of ArrayList traversals: § Identify standard algorithms. § Modify standard algorithms. § Develop an algorithm.
ESSENTIAL KNOWLEDGE	CON-2.J.1 There are standard ArrayList algorithms that utilize traversals to: § Insert elements § Delete elements § Apply the same standard algorithms that are used with 1D arrays	CON-2.J.2 Some algorithms require multiple String, array, or ArrayList objects to be traversed simultaneously

7.5 Searching

TOPIC	7.5 Searching
ENDURING UNDERSTANDING	CON-2 Programmers incorporate iteration and selection into code as a way of providing instructions for the computer to process each of the many possible input values.
LEARNING OBJECTIVE	CON-2.K Apply sequential/linear search algorithms to search for specific information in array or ArrayList objects.
ESSENTIAL KNOWLEDGE	CON-2.K.1 There are standard algorithms for searching.	CON-2.K.2 Sequential/linear search algorithms check each element in order until the desired value is found or all elements in the array or ArrayList have been checked.

7.6 Sorting

TOPIC	7.6 Sorting
ENDURING UNDERSTANDING	CON-2 Programmers incorporate iteration and selection into code as a way of providing instructions for the computer to process each of the many possible input values.
LEARNING OBJECTIVE	CON-2.L Apply selection sort and insertion sort algorithms to sort the elements of array or ArrayList objects.	CON-2.M Compute statement execution counts and informal run-time comparison of sorting algorithms.
ESSENTIAL KNOWLEDGE	CON-2.L.1 Selection sort and insertion sort are iterative sorting algorithms that can be used to sort elements in an array or ArrayList.	CON-2.M.1 Informal run-time comparisons of program code segments can be made using statement execution counts.

7.7 Ethical Issues Around Data Collection

TOPIC	7.7 Ethical Issues Around Data Collection
ENDURING UNDERSTANDING	IOC-1 While programs are typically designed to achieve a specific purpose, they may have unintended consequences.
LEARNING OBJECTIVE	IOC-1.B Explain the risks to privacy from collecting and storing personal data on computer systems.
ESSENTIAL KNOWLEDGE	IOC-1.B.1 When using the computer, personal privacy is at risk. Programmers should attempt to safeguard personal privacy.	IOC-1.B.2 Computer use and the creation of programs have an impact on personal security. These impacts can be beneficial and/or harmful.

Activities

Sample Activities	Predict and compare Have students look at the code they wrote to solve the free-response question in Unit 6 (or other code from Unit 6) on paper, and have them rewrite it using an ArrayList. Have them highlight the parts that need to be changed and determine how to change them. Then, have students type up the changes in an IDE and confirm that the program still works as expected.
	Identify a subtask Have students read through an ArrayList-based free-response question in groups, and have them identify all subtasks. These subtasks could be conditional statements, iteration, or even other methods. Once the subtasks have been identified, divide the subtasks among the group members, and have students implement their given subtask. When all students are finished, have them combine the subtasks into a single solution.
	Discussion group Discuss the algorithm necessary to search for the smallest value in an ArrayList. Without explaining what you are doing, change the Boolean expression so that it will find the largest value, and ask students to describe what the resulting algorithm will do. Then, change the algorithm to store and return the location of the largest value, and discuss the change.

UNIT 8: 2D Array

Overview

AP EXAM WEIGHTING	7.5–10%
CLASS PERIODS	~10–12
OVERVIEW	In Unit 6, students learned how 1D arrays store large amounts of related data. These same concepts will be implemented with two-dimensional (2D) arrays in this unit. A 2D array is most suitable to represent a table. Each table element is accessed using the variable name and row and column indices. Unlike 1D arrays, 2D arrays require nested iterative statements to traverse and access all elements. The easiest way to accomplished this is in row-major order, but it is important to cover additional traversal patterns, such as back and forth or column-major.

8.1 2D Arrays

TOPIC	8.1 2D Arrays
ENDURING UNDERSTANDING	VAR-2 To manage large amounts of data or complex relationships in data, programmers write code that groups the data together into a single data structure without creating individual variables for each value.
LEARNING OBJECTIVE	VAR-2.F Represent collections of related primitive or object reference data using two-dimensional (2D) array objects.
ESSENTIAL KNOWLEDGE	VAR-2.F.1 2D arrays are stored as arrays of arrays. Therefore, the way 2D arrays are created and indexed is similar to 1D array objects. X EXCLUSION STATEMENT—(EK VAR-2.F.1): 2D array objects that are not rectangular are outside the scope of the course and AP Exam.	VAR-2.F.2 For the purposes of the exam, when accessing the element at arr[first][second], the first index is used for rows, the second index is used for columns.	VAR-2.F.3 The initializer list used to create and initialize a 2D array consists of initializer lists that represent 1D arrays.	VAR-2.F.4 The square brackets [row][col] are used to access and modify an element in a 2D array.	VAR-2.F.5 “Row-major order” refers to an ordering of 2D array elements where traversal occurs across each row, while “column-major order” traversal occurs down each column.

8.2 Traversing 2D Arrays

TOPIC	8.2 Traversing 2D Arrays
ENDURING UNDERSTANDING	VAR-2 To manage large amounts of data or complex relationships in data, programmers write code that groups the data together into a single data structure without creating individual variables for each value.			CON-2 Programmers incorporate iteration and selection into code as a way of providing instructions for the computer to process each of the many possible input values.
LEARNING OBJECTIVE	VAR-2.G For 2D array objects: § Traverse using nested for loops. § Traverse using nested enhanced for loops.			CON-2.N For algorithms in the context of a particular specification that requires the use of 2D array traversals: § Identify standard algorithms. § Modify standard algorithms. § Develop an algorithm.
ESSENTIAL KNOWLEDGE	VAR-2.G.1 Nested iteration statements are used to traverse and access all elements in a 2D array. Since 2D arrays are stored as arrays of arrays, the way 2D arrays are traversed using for loops and enhanced for loops is similar to 1D array objects.	VAR-2.G.2 Nested iteration statements can be written to traverse the 2D array in “row-major order” or “column-major order.”	VAR-2.G.3 The outer loop of a nested enhanced for loop used to traverse a 2D array traverses the rows. Therefore, the enhanced for loop variable must be the type of each row, which is a 1D array. The inner loop traverses a single row. Therefore, the inner enhanced for loop variable must be the same type as the elements stored in the 1D array	CON-2.N.1 When applying sequential/linear search algorithms to 2D arrays, each row must be accessed then sequential/linear search applied to each row of a 2D array	CON-2.N.2 All standard 1D array algorithms can be applied to 2D array objects.

Activities

Sample Activities	Using manipulatives Use different-sized egg cartons or ice cube trays with random compartments filled with small toys or candy. Create laminated cards with the code for the construction of, and access to, a 2D array, leaving blanks for the name and size dimensions. Have students fill in the missing code that would be used to represent the physical 2D array objects and access the randomly stored elements
	Activating prior knowledge When first introducing 2D arrays and row-major traversal, ask students which part of the nested for loop structure loops over a 1D array. Based on what they know about the traversal of 1D array structures, ask them to calculate the number of times the inner loop executes.
	Sharing and responding As a class, create a set of test cases to be used with answers to a free-response question. Have students write their answers to the free-response question individually on paper. After exchanging solutions with another student, ask students to find errors or validate results of their peers’ code by tracing the code with the developed test cases. Allow students an opportunity to provide feedback on the program code as well as the results of each test case.

UNIT 9: Inheritance

Overview

AP EXAM WEIGHTING	5–10%
CLASS PERIODS	~14–15
OVERVIEW	Creating objects, calling methods on the objects created, and being able to define a new data type by creating a class are essential understandings before moving into this unit. One of the strongest advantages of Java is the ability to categorize classes into hierarchies through inheritance. Certain existing classes can be extended to include new behaviors and attributes without altering existing code. These newly created classes are called subclasses. In this unit, students will learn how to recognize common attributes and behaviors that can be used in a superclass and will then create a hierarchy by writing subclasses to extend a superclass. Recognizing and utilizing existing hierarchies will help students create more readable and maintainable programs.

9.1 Creating Superclasses and Subclasses

TOPIC	9.1 Creating Superclasses and Subclasses
ENDURING UNDERSTANDING	MOD-3 When multiple classes contain common attributes and behaviors, programmers create a new class containing the shared attributes and behaviors forming a hierarchy. Modifications made at the highest level of the hierarchy apply to the subclasses.
LEARNING OBJECTIVE	MOD-3.B Create an inheritance relationship from a subclass to the superclass.
ESSENTIAL KNOWLEDGE	MOD-3.B.1 A class hierarchy can be developed by putting common attributes and behaviors of related classes into a single class called a superclass.	MOD-3.B.2 Classes that extend a superclass, called subclasses, can draw upon the existing attributes and behaviors of the superclass without repeating these in the code.	MOD-3.B.3 Extending a subclass from a superclass creates an “is-a” relationship from the subclass to the superclass.	MOD-3.B.4 The keyword extends is used to establish an inheritance relationship between a subclass and a superclass. A class can extend only one superclass.

9.2 Writing Constructors for Subclasses

TOPIC	9.2 Writing Constructors for Subclasses
ENDURING UNDERSTANDING	MOD-3 When multiple classes contain common attributes and behaviors, programmers create a new class containing the shared attributes and behaviors forming a hierarchy. Modifications made at the highest level of the hierarchy apply to the subclasses.
LEARNING OBJECTIVE	MOD-3.B Create an inheritance relationship from a subclass to the superclass.
ESSENTIAL KNOWLEDGE	MOD-3.B.5 Constructors are not inherited.	MOD-3.B.6 The superclass constructor can be called from the first line of a subclass constructor by using the keyword super and passing appropriate parameters.	MOD-3.B.7 The actual parameters passed in the call to the superclass constructor provide values that the constructor can use to initialize the object’s instance variables.	MOD-3.B.8 When a subclass’s constructor does not explicitly call a superclass’s constructor using super, Java inserts a call to the superclass’s no-argument constructor.	MOD-3.B.9 Regardless of whether the superclass constructor is called implicitly or explicitly, the process of calling superclass constructors continues until the Object constructor is called. At this point, all of the constructors within the hierarchy execute beginning with the Object constructor.

9.3 Overriding Methods

TOPIC	9.3 Overriding Methods
ENDURING UNDERSTANDING	MOD-3 When multiple classes contain common attributes and behaviors, programmers create a new class containing the shared attributes and behaviors forming a hierarchy. Modifications made at the highest level of the hierarchy apply to the subclasses.
LEARNING OBJECTIVE	LEARNING OBJECTIVE MOD-3.B Create an inheritance relationship from a subclass to the superclass.
ESSENTIAL KNOWLEDGE	MOD-3.B.10 Method overriding occurs when a public method in a subclass has the same method signature as a public method in the superclass.	MOD-3.B.11 Any method that is called must be defined within its own class or its superclass.	MOD-3.B.12 A subclass is usually designed to have modified (overridden) or additional methods or instance variables.	MOD-3.B.13 A subclass will inherit all public methods from the superclass; these methods remain public in the subclass.

9.4 super Keyword

TOPIC	9.4 super Keyword
ENDURING UNDERSTANDING	MOD-3 When multiple classes contain common attributes and behaviors, programmers create a new class containing the shared attributes and behaviors forming a hierarchy. Modifications made at the highest level of the hierarchy apply to the subclasses.
LEARNING OBJECTIVE	MOD-3.B Create an inheritance relationship from a subclass to the superclass.
ESSENTIAL KNOWLEDGE	MOD-3.B.14 The keyword super can be used to call a superclass’s constructors and methods.	MOD-3.B.15 The superclass method can be called in a subclass by using the keyword super with the method name and passing appropriate parameters.

9.5 Creating References Using Inheritance Hierarchies

TOPIC	9.5 Creating References Using Inheritance Hierarchies
ENDURING UNDERSTANDING	MOD-3 When multiple classes contain common attributes and behaviors, programmers create a new class containing the shared attributes and behaviors forming a hierarchy. Modifications made at the highest level of the hierarchy apply to the subclasses.
LEARNING OBJECTIVE	MOD-3.C Define reference variables of a superclass to be assigned to an object of a subclass in the same hierarchy.
ESSENTIAL KNOWLEDGE	MOD-3.C.1 When a class S “is-a” class T, T is referred to as a superclass, and S is referred to as a subclass.	MOD-3.C.2 If S is a subclass of T, then assigning an object of type S to a reference of type T facilitates polymorphism.	MOD-3.C.3 If S is a subclass of T, then a reference of type T can be used to refer to an object of type T or S.	MOD-3.C.4 Declaring references of type T, when S is a subclass of T, is useful in the following declarations: § Formal method parameters § arrays — T[] var ArrayList<T> var

9.6 Polymorphism

TOPIC	9.6 Polymorphism
ENDURING UNDERSTANDING	MOD-3 When multiple classes contain common attributes and behaviors, programmers create a new class containing the shared attributes and behaviors forming a hierarchy. Modifications made at the highest level of the hierarchy apply to the subclasses.
LEARNING OBJECTIVE	MOD-3.D Call methods in an inheritance relationship.
ESSENTIAL KNOWLEDGE	MOD-3.D.1 Utilize the Object class through inheritance.	MOD-3.D.2 At compile time, methods in or inherited by the declared type determine the correctness of a non-static method call.	MOD-3.D.3 At run-time, the method in the actual object type is executed for a non-static method call.

9.7 Object Superclass

TOPIC	9.7 Object Superclass
ENDURING UNDERSTANDING	MOD-3 When multiple classes contain common attributes and behaviors, programmers create a new class containing the shared attributes and behaviors forming a hierarchy. Modifications made at the highest level of the hierarchy apply to the subclasses.
LEARNING OBJECTIVE	MOD-3.E Call Object class methods through inheritance.
ESSENTIAL KNOWLEDGE	MOD-3.E.1 The Object class is the superclass of all other classes in Java.	MOD-3.E.2 The Object class is part of the java.lang package	MOD-3.E.3 The following Object class methods and constructors—including what they do and when they are used—are part of the Java Quick Reference: § boolean equals(Object other) § String toString()	MOD-3.E.4 Subclasses of Object often override the equals and toString methods with classspecific implementations.

Activities

Sample Activities	Activating prior knowledge Have students review what they know about classes, methods, and the scope of variables by having them write a class based on specifications that can easily be extended by subclasses. This class will become the superclass for subclasses they write later in the unit.
	Create a plan Given a class design problem that requires the use of multiple classes in an inheritance hierarchy, students identify the common attributes and behaviors among these classes and write these into a superclass. Any additional information that does not belong in the superclass will be categorized to determine the additional classes that might be necessary and what methods will need to be added or overridden in the subclasses.
	Think aloud Provide students with a code segment that contains method calls using the super keyword. Have students describe the code segment out loud to themselves. Give students several individual statements that attempt to interact with the given code segment, and have them talk through each one, describing which statements would work and which ones would not, as well as the reasons why those statements wouldn’t work.
	Student response system Provide students with several statements where objects are created and the reference type and object type are different but related. Then provide students with calls to methods on these created objects. Use a student response system to have students determine whether each statement is legal, would result in a compile-time error, or would result in a run-time error.

UNIT 10: Recursion

Overview

AP EXAM WEIGHTING	5–7.5%
CLASS PERIODS	~3–5
OVERVIEW	Sometimes a problem can be solved by solving smaller or simpler versions of the same problem rather than attempting an iterative solution. This is called recursion, and it is a powerful math and computer science idea. In this unit, students will revisit how control is passed when methods are called, which is necessary knowledge when working with recursion. Tracing skills introduced in Unit 2 are helpful for determining the purpose or output of a recursive method. In this unit, students will learn how to write simple recursive methods and determine the purpose or output of a recursive method by tracing.

10.1 Recursion

TOPIC	10.1 Recursion
ENDURING UNDERSTANDING	CON-2 Programmers incorporate iteration and selection into code as a way of providing instructions for the computer to process each of the many possible input values.
LEARNING OBJECTIVE	CON-2.O Determine the result of executing recursive methods.
ESSENTIAL KNOWLEDGE	CON-2.O.1 A recursive method is a method that calls itself	CON-2.O.2 Recursive methods contain at least one base case, which halts the recursion, and at least one recursive call.	CON-2.O.3 Each recursive call has its own set of local variables, including the formal parameters.	CON-2.O.4 Parameter values capture the progress of a recursive process, much like loop control variable values capture the progress of a loop.	CON-2.O.5 Any recursive solution can be replicated through the use of an iterative approach. X EXCLUSION STATEMENT—(EK CON-2.O.5): Writing recursive program code is outside the scope of the course and AP Exam.	CON-2.O.6 Recursion can be used to traverse String, array, and ArrayList objects.

10.2 Recursive Searching and Sorting

TOPIC	10.2 Recursive Searching and Sorting
ENDURING UNDERSTANDING	CON-2 Programmers incorporate iteration and selection into code as a way of providing instructions for the computer to process each of the many possible input values.
LEARNING OBJECTIVE	CON-2.P Apply recursive search algorithms to information in String, 1D array, or ArrayList objects.				CON-2.Q Apply recursive algorithms to sort elements of array or ArrayList objects.
ESSENTIAL KNOWLEDGE	CON-2.P.1 Data must be in sorted order to use the binary search algorithm.	CON-2.P.2 The binary search algorithm starts at the middle of a sorted array or ArrayList and eliminates half of the array or ArrayList in each iteration until the desired value is found or all elements have been eliminated.	CON-2.P.3 Binary search can be more efficient than sequential/linear search. X EXCLUSION STATEMENT—(EK CON-2.P.3): Search algorithms other than sequential/linear and binary search are outside the scope of the course and AP Exam.	CON-2.P.4 The binary search algorithm can be written either iteratively or recursively.	CON-2.Q.1 Merge sort is a recursive sorting algorithm that can be used to sort elements in an array or ArrayList.

Activities

Sample Activities	Sharing and responding Provide students with the pseudocode to multiple recursive algorithms, and have students write the base case of the recursive methods and share it with their partner. The partner should then provide feedback, including any corrections or additions that may be needed.
	Look for a pattern Provide students with a recursive method and several different inputs. Have students run the recursive method, record the various outputs, and look for a pattern between the input and related output. Ask students to write one or two sentences as a broad description of what the recursive method is doing.
	Code tracing When looking at a recursive method to determine how many times it executes, have students create a call tree or a stack trace to show the method being called and the values of any parameters of each call. Students can then count up the number of times a statement executes or a method is called.

UNIT 1: CREATIVE DEVELOPMENT (CRD)

Overview

AP EXAM WEIGHTING	10–13%
CLASS PERIODS	~17
OVERVIEW	Collaboration is crucial when developing computing innovations, because having multiple perspectives offers opportunities to improve the design of innovations. In this big idea, students work collaboratively to design and develop programs using an iterative development process. They identify the needs of all users by gathering input from people from different backgrounds and demographics. Once the program is developed, they test it to ensure it meets these needs. Effective collaboration can often differ from group work, because it requires equal participation and voice from all members of the group. Early in the school year, it may be helpful for teachers to establish practices and norms that facilitate a collaborative environment and provide students with time to practice working together. Content in this big idea is often paired with Big Idea 3: Algorithms and Programming.
Essential Questions	CRD-1 How has working collaboratively with other students improved an overall project? What are some ways you can collect additional feedback on your program to use for improvements? CRD-2 What are some ways you currently plan your work before starting a project? What apps or programs have you stopped using because you didn't like the design of how you interacted with it?

1.1 Collaboration

TOPIC	1.1 Collaboration
ENDURING UNDERSTANDING	CRD-1 Incorporating multiple perspectives through collaboration improves computing innovations as they are developed.
LEARNING OBJECTIVE	CRD-1.A Explain how computing innovations are improved through collaboration. 1.C						CRD-1.B Explain how computing innovations are developed by groups of people.‚ 1.C		CRD-1.C Demonstrate effective interpersonal skills during collaboration.‚ 1.C
ESSENTIAL KNOWLEDGE	CRD-1.A.1 A computing innovation includes a program as an integral part of its function.	CRD-1.A.2 A computing innovation can be physical (e.g., self-driving car), nonphysical computing software (e.g., picture editing software), or a nonphysical computing concept (e.g., e-commerce).	CRD-1.A.3 Effective collaboration produces a computing innovation that reflects the diversity of talents and perspectives of those who designed it.	CRD-1.A.4 Collaboration that includes diverse perspectives helps avoid bias in the development of computing innovations.	CRD-1.A.5 Consultation and communication with users are important aspects of the development of computing innovations.	CRD-1.A.6 Information gathered from potential users can be used to understand the purpose of a program from diverse perspectives and to develop a program that fully incorporates these perspectives.	CRD-1.B.1 Online tools support collaboration by allowing programmers to share and provide feedback on ideas and documents.	CRD-1.B.2 Common models such as pair programming exist to facilitate collaboration.	CRD-1.C.1 Effective collaborative teams practice interpersonal skills, including but not limited to: communication consensus building conflict resolution negotiation

1.2 Program Function and Purpose

TOPIC	1.2 Program Function and Purpose
ENDURING UNDERSTANDING	CRD-2 Developers create and innovate using an iterative design process that is userfocused, that incorporates implementation/feedback cycles, and that leaves ample room for experimentation and risk-taking.
LEARNING OBJECTIVE	CRD-2.A Describe the purpose of a computing innovation.‚ 1.A	CRD-2.B Explain how a program or code segment functions. 4.A	CRD-2.C Identify input(s) to a program.‚ 3.A	CRD-2.D Identify output(s) produced by a program.‚ 3.A
ESSENTIAL KNOWLEDGE	CRD-2.A.1 The purpose of computing innovations is to solve problems or to pursue interests through creative expression. CRD-2.A.2 An understanding of the purpose of a computing innovation provides developers with an improved ability to develop that computing innovation.	CRD-2.B.1 A program is a collection of program statements that performs a specific task when run by a computer. A program is often referred to as software. CRD-2.B.2 A code segment is a collection of program statements that is part of a program. CRD-2.B.3 A program needs to work for a variety of inputs and situations. CRD-2.B.4 The behavior of a program is how a program functions during execution and is often described by how a user interacts with it. CRD-2.B.5 A program can be described broadly by what it does, or in more detail by both what the program does and how the program statements accomplish this function.	CRD-2.C.1 Program inputs are data sent to a computer for processing by a program. Input can come in a variety of forms, such as tactile, audio, visual, or text. CRD-2.C.2 An event is associated with an action and supplies input data to a program. CRD-2.C.3 Events can be generated when a key is pressed, a mouse is clicked, a program is started, or any other defined action occurs that affects the flow of execution. CRD-2.C.4 Inputs usually affect the output produced by a program. CRD-2.C.5 In event-driven programming, program statements are executed when triggered rather than through the sequential flow of control. CRD-2.C.6 Input can come from a user or other programs.	CRD-2.D.1 Program outputs are any data sent from a program to a device. Program output can come in a variety of forms, such as tactile, audio, visual, or text. CRD-2.D.2 Program output is usually based on a program's input or prior state (e.g., internal values).

1.3 Program Design and Development

TOPIC	1.3 Program Design and Development
ENDURING UNDERSTANDING	CRD-2 Developers create and innovate using an iterative design process that is userfocused, that incorporates implementation/feedback cycles, and that leaves ample room for experimentation and risk-taking.
LEARNING OBJECTIVE	CRD-2.E Develop a program using a development process.‚ 1.B	CRD-2.F Design a program and its user interface.‚ 1.B	CRD-2.G Describe the purpose of a code segment or program by writing documentation.‚ 4.A	CRD-2.H Acknowledge code segments used from other sources.‚ 1.C
ESSENTIAL KNOWLEDGE	CRD-2.E.1 A development process can be ordered and intentional, or exploratory in nature. CRD-2.E.2 There are multiple development processes. The following phases are commonly used when developing a program: investigating and reflecting designing prototyping testing CRD-2.E.3 A development process that is iterative requires refinement and revision based on feedback, testing, or reflection throughout the process. This may require revisiting earlier phases of the process. CRD-2.E.4 A development process that is incremental is one that breaks the problem into smaller pieces and makes sure each piece works before adding it to the whole.	CRD-2.F.1 The design of a program incorporates investigation to determine its requirements. CRD-2.F.2 Investigation in a development process is useful for understanding and identifying the program constraints, as well as the concerns and interests of the people who will use the program. CRD-2.F.3 Some ways investigation can be performed are as follows: collecting data through surveys user testing interviews direct observations CRD-2.F.4 Program requirements describe how a program functions and may include a description of user interactions that a program must provide. CRD-2.F.5 A program's specification defines the requirements for the program. CRD-2.F.6 In a development process, the design phase outlines how to accomplish a given program specification. CRD-2.F.7 The design phase of a program may include: brainstorming planning and storyboarding organizing the program into modules and functional components creation of diagrams that represent the layouts of the user interface development of a testing strategy for the program	CRD-2.G.1 Program documentation is a written description of the function of a code segment, event, procedure, or program and how it was developed. CRD-2.G.2 Comments are a form of program documentation written into the program to be read by people and do not affect how a program runs. CRD-2.G.3 Programmers should document a program throughout its development. CRD-2.G.4 Program documentation helps in developing and maintaining correct programs when working individually or in collaborative programming environments. CRD-2.G.5 Not all programming environments support comments, so other methods of documentation may be required.	CRD-2.H.1 It is important to acknowledge any code segments that were developed collaboratively or by another source. CRD-2.H.2 Acknowledgement of a code segment(s) written by someone else and used in a program can be in the program documentation. The acknowledgement should include the origin or original author's name.

1.4 Identifying and Correcting Errors

TOPIC	1.4 Identifying and Correcting Errors
ENDURING UNDERSTANDING	CRD-2 Developers create and innovate using an iterative design process that is userfocused, that incorporates implementation/feedback cycles, and that leaves ample room for experimentation and risk-taking.
LEARNING OBJECTIVE	CRD-2.I For errors in an algorithm or program: a. Identify the error. 4.C b. Correct the Error. 4.C					CRD-2.J Identify inputs and corresponding expected outputs or behaviors that can be used to check the correctness of an algorithm or program.‚ 4.C
ESSENTIAL KNOWLEDGE	CRD-2.I.1 A logic error is a mistake in the algorithm or program that causes it to behave incorrectly or unexpectedly	CRD-2.I.2 A syntax error is a mistake in the program where the rules of the programming language are not followed.	CRD-2.I.3 A run-time error is a mistake in the program that occurs during the execution of a program. Programming languages define their own runtime errors.	CRD-2.I.4 An overflow error is an error that occurs when a computer attempts to handle a number that is outside of the defined range of values.	CRD-2.I.5 The following are effective ways to find and correct errors: test cases hand tracing visualizations debuggers adding extra output statement(s)	CRD-2.J.1 In the development process, testing uses defined inputs to ensure that an algorithm or program is producing the expected outcomes. Programmers use the results from testing to revise their algorithms or programs.	CRD-2.J.2 Defined inputs used to test a program should demonstrate the different expected outcomes that are at or just beyond the extremes (minimum and maximum) of input data.	CRD-2.J.3 Program requirements are needed to identify appropriate defined inputs for testing.

Activities

Sample Activities

Sharing and responding Have students develop a list of three questions that they would like to use data to answer. Then, in small groups, ask each student to share one of their questions. The group will respond with feedback to improve the focus and direction of the question. Students should take turns sharing their questions until all questions have been considered. Finally, ask each group to come to a consensus on which three questions they will answer with data.

Diagramming In small groups, have students play a board game for 10 minutes. As they play, ask them to record the actions (such as rolling the dice or moving their piece) and decisions made in a diagram or flowchart. Have students trade games with another group and play the game using the diagram for directions. Students should identify and correct where the diagram might not be accurate or have missing steps. See the Language and Logic of Computing: Algorithmic Thinking Teaching and Assessing Module in the Professional Learning section of AP Classroom for a more detailed lesson plan and video example.

UNIT 2: Data

Overview

AP EXAM WEIGHTING	17–22%
CLASS PERIODS	~19
OVERVIEW	Because essentially everything we do with a computer is being broken down into some form of data, it is important for students to develop a breadth of understanding of how computers handle data and how students can use those same data to solve problems such as raising awareness for a cause, using census data to determine which state will gain seats in the House of Representatives, or using traffic and cost data to determine the ideal location for prom. In this big idea, students will gain a deep understanding of how information is stored on a computer in binary and seamlessly translated into what is seen on the screen or heard through speakers. Students will also learn how data are processed to learn something new. This big idea is often paired with Big Idea 3: Algorithms and Programming and Big Idea 5: Impact of Computing.
ESSENTIAL QUESTIONS	DAT-1 How can we use 1s and 0s to represent something complex like a video of the marching band playing a song? DAT-2 How can you predict the attendance at a school event using data gathered from social media? When is it more appropriate to use a computer to analyze data than to complete the analysis by hand?

2.1 Binary Numbers

TOPIC	2.1 Binary Numbers
ENDURING UNDERSTANDING	DAT-1 The way a computer represents data internally is different from the way the data are interpreted and displayed for the user. Programs are used to translate data into a representation more easily understood by people.
LEARNING OBJECTIVE	DAT-1.A Explain how data can be represented using bits. 3.C	DAT-1.B Explain the consequences of using bits to represent data.‚ 1.D	DAT-1.C For binary numbers: Calculate the binary (base 2) equivalent of a positive integer (base 10) and vice versa.‚ 2.B b. Compare and order binary numbers.‚ 2.B
ESSENTIAL KNOWLEDGE	DAT-1.A.1 Data values can be stored in variables, lists of items, or standalone constants and can be passed as input to (or output from) procedures. DAT-1.A.2 Computing devices represent data digitally, meaning that the lowest-level components of any value are bits. DAT-1.A.3 Bit is shorthand for binary digit and is either 0 or 1. DAT-1.A.4 A byte is 8 bits. DAT-1.A.5 Abstraction is the process of reducing complexity by focusing on the main idea. By hiding details irrelevant to the question at hand and bringing together related and useful details, abstraction reduces complexity and allows one to focus on the idea. DAT-1.A.6 Bits are grouped to represent abstractions. These abstractions include, but are not limited to, numbers, characters, and color. DAT-1.A.7 The same sequence of bits may represent different types of data in different contexts. DAT-1.A.8 Analog data have values that change smoothly, rather than in discrete intervals, over time. Some examples of analog data include pitch and volume of music, colors of a painting, or position of a sprinter during a race. DAT-1.A.9 The use of digital data to approximate realworld analog data is an example of abstraction. DAT-1.A.10 Analog data can be closely approximated digitally using a sampling technique, which means measuring values of the analog signal at regular intervals called samples. The samples are measured to figure out the exact bits required to store each sample.	DAT-1.B.1 In many programming languages, integers are represented by a fixed number of bits, which limits the range of integer values and mathematical operations on those values. This limitation can result in overflow or other errors. DAT-1.B.2 Other programming languages provide an abstraction through which the size of representable integers is limited only by the size of the computer's memory; this is the case for the language defined in the exam reference sheet. DAT-1.B.3 In programming languages, the fixed number of bits used to represent real numbers limits the range and mathematical operations on these values; this limitation can result in round-off and other errors. Some real numbers are represented as approximations in computer storage. X EXCLUSION STATEMENT (EK DAT-1.B.3): Specific range limitations for real numbers are outside the scope of this course and the AP Exam.	DAT-1.C.1 Number bases, including binary and decimal, are used to represent data. DAT-1.C.2 Binary (base 2) uses only combinations of the digits zero and one. DAT-1.C.3 Decimal (base 10) uses only combinations of the digits 0 “ 9. DAT-1.C.4 As with decimal, a digit's position in the binary sequence determines its numeric value. The numeric value is equal to the bit's value (0 or 1) multiplied by the place value of its position. DAT-1.C.5 The place value of each position is determined by the base raised to the power of the position. Positions are numbered starting at the rightmost position with 0 and increasing by 1 for each subsequent position to the left.

2.2 Data Compression

TOPIC	2.2 Data Compression
ENDURING UNDERSTANDING	DAT-1 The way a computer represents data internally is different from the way the data are interpreted and displayed for the user. Programs are used to translate data into a representation more easily understood by people.
LEARNING OBJECTIVE	DAT-1.D Compare data compression algorithms to determine which is best in a particular context.‚ 1.D
ESSENTIAL KNOWLEDGE	DAT-1.D.1 Data compression can reduce the size (number of bits) of transmitted or stored data.	DAT-1.D.2 Fewer bits does not necessarily mean less information.	DAT-1.D.3 The amount of size reduction from compression depends on both the amount of redundancy in the original data representation and the compression algorithm applied.	DAT-1.D.4 Lossless data compression algorithms can usually reduce the number of bits stored or transmitted while guaranteeing complete reconstruction of the original data.	DAT-1.D.5 Lossy data compression algorithms can significantly reduce the number of bits stored or transmitted but only allow reconstruction of an approximation of the original data.	DAT-1.D.6 Lossy data compression algorithms can usually reduce the number of bits stored or transmitted more than lossless compression algorithms.	DAT-1.D.7 In situations where quality or ability to reconstruct the original is maximally important, lossless compression algorithms are typically chosen.	DAT-1.D.8 In situations where minimizing data size or transmission time is maximally important, lossy compression algorithms are typically chosen.

2.3 Extracting Information from Data

TOPIC	2.3 Extracting Information from Data
ENDURING UNDERSTANDING	DAT-2 Programs can be used to process data, which allows users to discover information and create new knowledge.
LEARNING OBJECTIVE	DAT-2.A Describe what information can be extracted from data.‚ 5.B	DAT-2.B Describe what information can be extracted from metadata.‚ 5.B	DAT-2.C Identify the challenges associated with processing data.‚ 5.D
ESSENTIAL KNOWLEDGE	DAT-2.A.1 Information is the collection of facts and patterns extracted from data. DAT-2.A.2 Data provide opportunities for identifying trends, making connections, and addressing problems. DAT-2.A.3 Digitally processed data may show correlation between variables. A correlation found in data does not necessarily indicate that a causal relationship exists. Additional research is needed to understand the exact nature of the relationship. DAT-2.A.4 Often, a single source does not contain the data needed to draw a conclusion. It may be necessary to combine data from a variety of sources to formulate a conclusion.	DAT-2.B.1 Metadata are data about data. For example, the piece of data may be an image, while the metadata may include the date of creation or the file size of the image. DAT-2.B.2 Changes and deletions made to metadata do not change the primary data. DAT-2.B.3 Metadata are used for finding, organizing, and managing information. DAT-2.B.4 Metadata can increase the effective use of data or data sets by providing additional information. DAT-2.B.5 Metadata allow data to be structured and organized.	DAT-2.C.1 The ability to process data depends on the capabilities of the users and their tools. DAT-2.C.2 Data sets pose challenges regardless of size, such as: the need to clean data incomplete data invalid data the need to combine data sources DAT-2.C.3 Depending on how data were collected, they may not be uniform. For example, if users enter data into an open field, the way they choose to abbreviate, spell, or capitalize something may vary from user to user. DAT-2.C.4 Cleaning data is a process that makes the data uniform without changing their meaning (e.g., replacing all equivalent abbreviations, spellings, and capitalizations with the same word). DAT-2.C.5 Problems of bias are often created by the type or source of data being collected. Bias is not eliminated by simply collecting more data. DAT-2.C.6 The size of a data set affects the amount of information that can be extracted from it. DAT-2.C.7 Large data sets are difficult to process using a single computer and may require parallel systems. DAT-2.C.8 Scalability of systems is an important consideration when working with data sets, as the computational capacity of a system affects how data sets can be processed and stored.

2.4 Using Programs with Data

TOPIC	2.4 Using Programs with Data
ENDURING UNDERSTANDING	DAT-2 Programs can be used to process data, which allows users to discover information and create new knowledge.
LEARNING OBJECTIVE	DAT-2.D Extract information from data using a program. 2.B						DAT-2.E Explain how programs can be used to gain insight and knowledge from data.‚ 5.B
ESSENTIAL KNOWLEDGE	DAT-2.D.1 Programs can be used to process data to acquire information.	DAT-2.D.2 Tables, diagrams, text, and other visual tools can be used to communicate insight and knowledge gained from data.	DAT-2.D.3 Search tools are useful for efficiently finding information.	DAT-2.D.4 Data filtering systems are important tools for finding information and recognizing patterns in data.	DAT-2.D.5 Programs such as spreadsheets help efficiently organize and find trends in information.	DAT-2.D.6 Some processes that can be used to extract or modify information from data include the following: transforming every element of a data set, such as doubling every element in a list, or adding a parent's email to every student record filtering a data set, such as keeping only the positive numbers from a list, or keeping only students who signed up for band from a record of all the students combining or comparing data in some way, such as adding up a list of numbers, or finding the student who has the highest GPA visualizing a data set through a chart, graph, or other visual representation	DAT-2.E.1 Programs are used in an iterative and interactive way when processing information to allow users to gain insight and knowledge about data.	DAT-2.E.2 Programmers can use programs to filter and clean digital data, thereby gaining insight and knowledge.	DAT-2.E.3 Combining data sources, clustering data, and classifying data are parts of the process of using programs to gain insight and knowledge from data.	DAT-2.E.4 Insight and knowledge can be obtained from translating and transforming digitally represented information.	DAT-2.E.5 Patterns can emerge when data are transformed using programs.

Activities

Sample Activities	Look for a pattern Provide students with a sentence or paragraph of compressed lossless text and a key. Have them look for patterns in their process of retrieving the original text and evaluate whether this is the best compression algorithm to use. Have them write down the patterns they see along with their evaluation and share these in a large group
	Diagramming Give students a question and a list of data. Have them diagram a process that could be used to answer the question using the data, making sure to include the input(s) of information and the output of the transformed data. Have students include an explanation of how the process represented in their diagram would work to find the solution.

UNIT 3: Algorithms and Programming

Overview

AP EXAM WEIGHTING	30–35%
CLASS PERIODS	~45
OVERVIEW	All programming languages, whether block-based or text-based, use similar programming structures and commands. Having a basic understanding of how these building blocks are combined to form algorithms and abstractions in one language makes it easier to apply these same understandings to other programming languages. This big idea focuses on determining the efficiency of algorithms, as well as writing and implementing algorithms in a program. This big idea can be paired with any of the other big ideas and taught throughout the school year.
ESSENTIAL QUESTIONS	AAP-1 How can we store data in a program to solve problems? AAP-2 What might happen if you completed the steps in your regular morning routine to get ready and go to school in a different order? How might the reordering affect the decisions you make each morning? AAP-3 How do video games group the different actions for a player based on what key is pressed on the keyboard or controller? How do apps group different actions together based on user interaction, such as pressing buttons? AAP-4 What types of problems can be solved more easily with a computer, and what types can be solved more easily without a computer? Why?

3.1 Variables and Assignments

TOPIC	3.1 Variables and Assignments
ENDURING UNDERSTANDING	AAP-1 To find specific solutions to generalizable problems, programmers represent and organize data in multiple ways.
LEARNING OBJECTIVE	AAP-1.A Represent a value with a variable. 3.A				AAP-1.B Determine the value of a variable as a result of an assignment.‚ 4.B
ESSENTIAL KNOWLEDGE	AAP-1.A.1 A variable is an abstraction inside a program that can hold a value. Each variable has associated data storage that represents one value at a time, but that value can be a list or other collection that in turn contains multiple values.	AAP-1.A.2 Using meaningful variable names helps with the readability of program code and understanding of what values are represented by the variables.	AAP-1.A.3 Some programming languages provide types to represent data, which are referenced using variables. These types include numbers, Booleans, lists, and strings.	AAP-1.A.4 Some values are better suited to representation using one type of datum rather than another	AAP-1.B.1 The assignment operator allows a program to change the value represented by a variable.	AAP-1.B.2 The exam reference sheet provides the "←" operator to use for assignment. For example: a←expression evaluates expression and then assigns a copy of the result to the variable a.	AAP-1.B.3 The value stored in a variable will be the most recent value assigned. For example: a←1 b←a a←2 display(b) still displays 1.

3.2 Data Abstraction

TOPIC	3.2 Data Abstraction
ENDURING UNDERSTANDING	AAP-1 To find specific solutions to generalizable problems, programmers represent and organize data in multiple ways.
LEARNING OBJECTIVE	AAP-1.C Represent a list or string using a variable.‚ 3.A				AAP-1.D For data abstraction: Develop data abstraction using lists to store multiple elements.‚ 3.B Explain how the use of data abstraction manages complexity in program code.‚ 3.C
ESSENTIAL KNOWLEDGE	AAP-1.C.1 A list is an ordered sequence of elements. For example, [value1, value2, value3, ...] describes a list where value1 is the first element, value2 is the second element, value3 is the third element, and so on.	AAP-1.C.2 An element is an individual value in a list that is assigned a unique index.	AAP-1.C.3 An index is a common method for referencing the elements in a list or string using natural numbers.	AAP-1.C.4 A string is an ordered sequence of characters.	AAP-1.D.1 Data abstraction provides a separation between the abstract properties of a data type and the concrete details of its representation.	AAP-1.D.2 Data abstractions manage complexity in programs by giving a collection of data a name without referencing the specific details of the representation.	AAP-1.D.3 Data abstractions can be created using lists.	AAP-1.D.4 Developing a data abstraction to implement in a program can result in a program that is easier to develop and maintain.	AAP-1.D.5 Data abstractions often contain different types of elements.	AAP-1.D.6 The use of lists allows multiple related items to be treated as a single value. Lists are referred to by different names, such as array, depending on the programming language.	AAP-1.D.7 The exam reference sheet provides the notation [value1, value2, value3, ...] to create a list with those values as the first, second, third, and so on items. For example, Text: aList←[value1, value2, value3, ...] creates a new list that contains the values value1, value2, value3, and ... at indices 1, 2, 3, and ... respectively and assigns it to aList. Text: aList ←[] creates a new empty list and assigns it to aList. Text: aList←bList assigns a copy of the list bList to the list aList. For example, if bList contains [20, 40, 60], then aList will also contain [20, 40, 60] after the assignment.	AAP-1.D.8 The exam reference sheet describes a list structure whose index values are 1 through the number of elements in the list, inclusive. For all list operations, if a list index is less than 1 or greater than the length of the list, an error message is produced and the program will terminate.

3.3 Mathematical Expressions

TOPIC	3.3 Mathematical Expressions
ENDURING UNDERSTANDING	AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.A Express an algorithm that uses sequencing without using a programming language.‚ 2.A	AAP-2.B Represent a step-by-step algorithmic process using sequential code statements. 2.B	AAP-2.C Evaluate expressions that use arithmetic operators.‚ 4.B
ESSENTIAL KNOWLEDGE	AAP-2.A.1 An algorithm is a finite set of instructions that accomplish a specific task. AAP-2.A.2 Beyond visual and textual programming languages, algorithms can be expressed in a variety of ways, such as natural language, diagrams, and pseudocode. AAP-2.A.3 Algorithms executed by programs are implemented using programming languages. AAP-2.A.4 Every algorithm can be constructed using combinations of sequencing, selection, and iteration.	AAP-2.B.1 Sequencing is the application of each step of an algorithm in the order in which the code statements are given. AAP-2.B.2 A code statement is a part of program code that expresses an action to be carried out. AAP-2.B.3 An expression can consist of a value, a variable, an operator, or a procedure call that returns a value. AAP-2.B.4 Expressions are evaluated to produce a single value. AAP-2.B.5 The evaluation of expressions follows a set order of operations defined by the programming language. AAP-2.B.6 Sequential statements execute in the order they appear in the code segment. AAP-2.B.7 Clarity and readability are important considerations when expressing an algorithm in a programming language.	AAP-2.C.1 Arithmetic operators are part of most programming languages and include addition, subtraction, multiplication, division, and modulus operators. AAP-2.C.2 The exam reference sheet provides a MOD b, which evaluates to the remainder when a is divided by b. Assume that a is an integer greater than or equal to 0 and b is an integer greater than 0. For example, 17 MOD 5 evaluates to 2. AAP-2.C.3 The exam reference sheet provides the arithmetic operators +, -, *, /, and MOD. Text: a + b a - b a * b a / b a MOD b These are used to perform arithmetic on a and b. For example, 17 / 5 evaluates to 3.4. AAP-2.C.4 The order of operations used in mathematics applies when evaluating expressions. The MOD operator has the same precedence as the * and / operators. DAT-2.C.5 Problems of bias are often created by the type or source of data being collected. Bias is not eliminated by simply collecting more data.

3.4 Strings

TOPIC	3.4 Strings
ENDURING UNDERSTANDING	AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.D Evaluate expressions that manipulate strings.‚ 4.B
ESSENTIAL KNOWLEDGE	AAP-2.D.1 String concatenation joins together two or more strings end-to-end to make a new string.	AAP-2.D.2 A substring is part of an existing string.

3.5 Boolean Expressions

TOPIC	3.5 Boolean Expressions
ENDURING UNDERSTANDING	AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.E For relationships between two variables, expressions, or values: Write expressions using relational operators. 2B Evaluate expressions using relational operators. 4B		AAP-2.F For relationships between Boolean values: Write expressions that use logical operators. 2.B Evaluate expressions that use logic operators.‚ 4.B
ESSENTIAL KNOWLEDGE	AAP-2.E.1 A Boolean value is either true or false.	AAP-2.E.2 The exam reference sheet provides the following relational operators: =, ≠, >, <, ≥, and ≤. Text and Block: a = b a ≠ b a > b a < b a ≤ b a ≥ b These are used to test the relationship between two variables, expressions, or values. A comparison using a relational operator evaluates to a Boolean value. For example, a = b evaluates to true if a and b are equal; otherwise, it evaluates to false.	AAP-2.F.1 The exam reference sheet provides the logical operators NOT, AND, and OR, which evaluate to a Boolean value.	AAP-2.F.2 The exam reference sheet provides Text: NOT condition which evaluates to true if condition is false; otherwise it evaluates to false.	AAP-2.F.3 The exam reference sheet provides Text: condition1 AND condition2 which evaluates to true if both condition1 and condition2 are true; otherwise it evaluates to false.	AAP-2.F.4 The exam reference sheet provides Text: condition1 OR condition2 which evaluates to true if condition1 is true or if condition2 is true or if both condition1 and condition2 are true; otherwise it evaluates to false.	AAP-2.F.5 The operand for a logical operator is either a Boolean expression or a single Boolean value.

3.6 Conditionals

TOPIC	3.6 Conditionals
ENDURING UNDERSTANDING	AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.G Express an algorithm that uses selection without using a programming language.‚ 2.A	AAP-2.H For selection: Write conditional statements. 2.B Determine the result of conditional statements. 4.B
ESSENTIAL KNOWLEDGE	AAP-2.G.1 Selection determines which parts of an algorithm are executed based on a condition being true or false.	AAP-2.H.1 Conditional statements, or if-statements, affect the sequential flow of control by executing different statements based on the value of a Boolean expression.	AAP-2.H.2 The exam reference sheet provides Text: IF(condition) { <block of statements> } in which the code in block of statements is executed if the Boolean expression condition evaluates to true; no action is taken if condition evaluates to false.	AAP-2.H.3 The exam reference sheet provides Text: IF(condition) { <first block of statements> } ELSE { <second block of statements> } in which the code in first block of statements is executed if the Boolean expression condition evaluates to true; otherwise, the code in second block of statements is executed.

3.7 Nested Conditionals

TOPIC	3.7 Nested Conditionals
ENDURING UNDERSTANDING	ENDURING UNDERSTANDING AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.I For nested selection: Write nested conditional statements. 2.B b. Determine the result of nested conditional statements. 4.B
ESSENTIAL KNOWLEDGE	AAP-2.I.1 Nested conditional statements consist of conditional statements within conditional statements.

3.8 Iteration

TOPIC	3.8 Iteration
ENDURING UNDERSTANDING	AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.J Express an algorithm that uses iteration without using a programming language.‚ 2.A	AAP-2.K For iteration: Write iteration statements 2.B Determine the result or side effect of iteration statements. 4.B
ESSENTIAL KNOWLEDGE	AAP-2.J.1 Iteration is a repeating portion of an algorithm. Iteration repeats a specified number of times or until a given condition is met.	AAP-2.K.1 Iteration statements change the sequential flow of control by repeating a set of statements zero or more times, until a stopping condition is met.	AAP-2.K.2 The exam reference sheet provides Text: REPEAT n TIMES { <block of statements> } in which the block of statements is executed n times.	AAP-2.K.3 The exam reference sheet provides Text: REPEAT UNTIL(condition) { <block of statements> } in which the code in block of statements is repeated until the Boolean expression condition evaluates to true.	AAP-2.K.4 In REPEAT UNTIL(condition) iteration, an infinite loop occurs when the ending condition will never evaluate to true.	AAP-2.K.5 In REPEAT UNTIL(condition) iteration, if the conditional evaluates to true initially, the loop body is not executed at all, due to the condition being checked before the loop.

3.9 Developing Algorithms

TOPIC	3.9 Developing Algorithms
ENDURING UNDERSTANDING	AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.L Compare multiple algorithms to determine if they yield the same side effect or result.‚ 1.D					AAP-2.M For algorithms: Create algorithms. 2.A Combine and modify existing algroitms. 2.B
ESSENTIAL KNOWLEDGE	AAP-2.L.1 Algorithms can be written in different ways and still accomplish the same tasks.	AAP-2.L.2 Algorithms that appear similar can yield different side effects or results.	AAP-2.L.3 Some conditional statements can be written as equivalent Boolean expressions.	AAP-2.L.4 Some Boolean expressions can be written as equivalent conditional statements.	AAP-2.L.5 Different algorithms can be developed or used to solve the same problem.	AAP-2.M.1 Algorithms can be created from an idea, by combining existing algorithms, or by modifying existing algorithms.	AAP-2.M.2 Knowledge of existing algorithms can help in constructing new ones. Some existing algorithms include: determining the maximum or minimum value of two or more numbers computing the sum or average of two or more numbers identifying if an integer is or is not evenly divisible by another integer determining a robot's path through a maze	AAP-2.M.3 Using existing correct algorithms as building blocks for constructing another algorithm has benefits such as reducing development time, reducing testing, and simplifying the identification of errors.

3.10 Lists

TOPIC	3.10 Lists
ENDURING UNDERSTANDING	AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.N For list operations: Write expressions that use list indexing and list procedures.‚ 2.B Evaluate expressions that use list indexing and list procedures.‚ 4.B		AAP-2.O For algorithms involving elements of a list: Write iteration statements that traverse a list. 2.B Determine the result of an algoritms that includes list traversal. 4.B
ESSENTIAL KNOWLEDGE	AAP-2.N.1 The exam reference sheet provides basic operations on lists, including: accessing an element by index Text: aList[i] accesses the element of aList at index i. The first element of aList is at index 1 and is accessed using the notation aList[1]. assigning a value of an element of a list to a variable Text: x←aList [i] assigns the value of aList[i] to the variable x. assigning a value to an element of a list Text: aList[i]←x assigns the value of x to aList[i]. Text: aList[i]←aList[j] assigns the value of aList[j] to aList[i]. inserting elements at a given index Text: INSERT(aList, i, value) shifts to the right any values in aList at indices greater than or equal to i. The length of the list is increased by 1, and value is placed at index i in aList. adding elements to the end of the list Text: APPEND(aList, value) increases the length of aList by 1, and value is placed at the end of aList. removing elements Text: REMOVE(aList, i) removes the item at index i in aList and shifts to the left any values at indices greater than i. The length of aList is decreased by 1. determining the length of a list Text: LENGTH(aList) evaluates to the number of elements currently in aList.	AAP-2.N.2 List procedures are implemented in accordance with the syntax rules of the programming language.	AAP-2.O.1 Traversing a list can be a complete traversal, where all elements in the list are accessed, or a partial traversal, where only a portion of elements are accessed.	AAP-2.O.2 Iteration statements can be used to traverse a list.	AAP-2.O.3 The exam reference sheet provides Text: FOR EACH item IN aList { <block of statements> } The variable item is assigned the value of each element of aList sequentially, in order, from the first element to the last element. The code in block of statements is executed once for each assignment of item.	AAP-2.O.4 Knowledge of existing algorithms that use iteration can help in constructing new algorithms. Some examples of existing algorithms that are often used with lists include: determining a minimum or maximum value in a list computing a sum or average of a list of numbers	AAP-2.O.5 Linear search or sequential search algorithms check each element of a list, in order, until the desired value is found or all elements in the list have been checked.

3.11 Binary Search

TOPIC	3.11 Binary Search
ENDURING UNDERSTANDING	AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.P For binary search algorithms: Determine the number of iterations required to find a value in a data set. 1.D Explain the requirements necessary to complete a binary search.‚ 1.A
ESSENTIAL KNOWLEDGE	AAP-2.P.1 The binary search algorithm starts at the middle of a sorted data set of numbers and eliminates half of the data; this process repeat until the desired value is found or all elements have been eliminated.	AAP-2.P.2 Data must be in sorted order to use the binary search algorithm.	AAP-2.P.3 Binary search is often more efficient than sequential/linear search when applied to sorted data.

3.12 Calling Procedures

TOPIC	3.12 Calling Procedures
ENDURING UNDERSTANDING	AAP-3 Programmers break down problems into smaller and more manageable pieces. By creating procedures and leveraging parameters, programmers generalize processes that can be reused. Procedures allow programmers to draw upon existing code that has already been tested, allowing them to write programs more quickly and with more confidence.
LEARNING OBJECTIVE	AAP-3.A For procedure calls: Write statements to call procedures 3.B Determine the result or effect of a procedure call 4.B
ESSENTIAL KNOWLEDGE	AAP-3.A.1 A procedure is a named group of programming instructions that may have parameters and return values.	AAP-3.A.2 Procedures are referred to by different names, such as method or function, depending on the programming language.	AAP-3.A.3 Parameters are input variables of a procedure. Arguments specify the values of the parameters when a procedure is called.	AAP-3.A.4 A procedure call interrupts the sequential execution of statements, causing the program to execute the statements within the procedure before continuing. Once the last statement in the procedure (or a return statement) has executed, flow of control is returned to the point immediately following where the procedure was called.	AAP-3.A.5 The exam reference sheet provides procName(arg1, arg2, ...) as a way to call Text: PROCEDURE procName(parameter1, parameter2, ...) { <block of statements> } which takes zero or more arguments; arg1 is assigned to parameter1, arg2 is assigned to parameter2, and so on.	AAP-3.A.6 The exam reference sheet provides the procedure Text: DISPLAY(expression) Block: to display the value of expression, followed by a space.	AAP-3.A.7 The exam reference sheet provides the Text: RETURN(expression) statement, which is used to return the flow of control to the point where the procedure was called and to return the value of expression.	AAP-3.A.8 The exam reference sheet provides result←procName(arg1, arg2, ...) to assign to result the value of the procedure being returned by calling Text: PROCEDURE procName(parameter1, parameter2, ...) { <block of statements> RETURN(expression) }	AAP-3.A.9 The exam reference sheet provides procedure Text: INPUT() which accepts a value from the user and returns the input value.

3.13 Developing Procedures

TOPIC	3.13 Developing Procedures
ENDURING UNDERSTANDING	AAP-3 Programmers break down problems into smaller and more manageable pieces. By creating procedures and leveraging parameters, programmers generalize processes that can be reused. Procedures allow programmers to draw upon existing code that has already been tested, allowing them to write programs more quickly and with more confidence
LEARNING OBJECTIVE	AAP-3.B Explain how the use of procedural abstraction manages complexity in a program.‚ 3.C							AAP-3.C Develop procedural abstractions to manage complexity in a program by writing procedures.‚ 3.B
ESSENTIAL KNOWLEDGE	AAP-3.B.1 One common type of abstraction is procedural abstraction, which provides a name for a process and allows a procedure to be used only knowing what it does, not how it does it.	AAP-3.B.2 Procedural abstraction allows a solution to a large problem to be based on the solutions of smaller subproblems. This is accomplished by creating procedures to solve each of the subproblems.	AAP-3.B.3 The subdivision of a computer program into separate subprograms is called modularity.	AAP-3.B.4 A procedural abstraction may extract shared features to generalize functionality instead of duplicating code. This allows for program code reuse, which helps manage complexity.	AAP-3.B.5 Using parameters allows procedures to be generalized, enabling the procedures to be reused with a range of input values or arguments.	AAP-3.B.6 Using procedural abstraction helps improve code readability.	AAP-3.B.7 Using procedural abstraction in a program allows programmers to change the internals of the procedure (to make it faster, more efficient, use less storage, etc.) without needing to notify users of the change as long as what the procedure does is preserved.	AAP-3.C.1 The exam reference sheet provides Text: PROCEDURE procName(parameter1, parameter2, ...) { <block of statements> } which is used to define a procedure that takes zero or more arguments. The procedure contains block of statements.	AAP-3.C.2 The exam reference sheet provides Text: PROCEDURE procName(parameter1, parameter2, ...) { <block of statements> RETURN(expression) } which is used to define a procedure that takes zero or more arguments. The procedure contains block of statements and returns the value of expression. The RETURN statement may appear at any point inside the procedure and causes an immediate return from the procedure back to the calling statement.

3.14 Libraries

TOPIC	3.14 Libraries
ENDURING UNDERSTANDING	AAP-3 Programmers break down problems into smaller and more manageable pieces. By creating procedures and leveraging parameters, programmers generalize processes that can be reused. Procedures allow programmers to draw upon existing code that has already been tested, allowing them to write programs more quickly and with more confidence.
LEARNING OBJECTIVE	AAP-3.D Select appropriate libraries or existing code segments to use in creating new programs.‚ 2.B
ESSENTIAL KNOWLEDGE	AAP-3.D.1 A software library contains procedures that may be used in creating new programs.	AAP-3.D.2 Existing code segments can come from internal or external sources, such as libraries or previously written code.	AAP-3.D.3 The use of libraries simplifies the task of creating complex programs.	AAP-3.D.4 Application program interfaces (APIs) are specifications for how the procedures in a library behave and can be used.	AAP-3.D.5 Documentation for an API/library is necessary in understanding the behaviors provided by the API/library and how to use them.

3.15 Random Values

TOPIC	3.15 Random Values
ENDURING UNDERSTANDING	AAP-3 Programmers break down problems into smaller and more manageable pieces. By creating procedures and leveraging parameters, programmers generalize processes that can be reused. Procedures allow programmers to draw upon existing code that has already been tested, allowing them to write programs more quickly and with more confidence
LEARNING OBJECTIVE	AAP-3.E For generating random values: Write expressions to generate possible values. 2.B Evaluate expressions to generate possible values. 4.B
ESSENTIAL KNOWLEDGE	AAP-3.E.1 The exam reference sheet provides Text: RANDOM(a, b) which generates and returns a random integer from a to b, inclusive. Each result is equally likely to occur. For example, RANDOM(1, 3) could return 1, 2, or 3.	AAP-3.E.2 Using random number generation in a program means each execution may produce a different result.

3.16 Simulations

TOPIC	3.16 Simulations
ENDURING UNDERSTANDING	AAP-3 Programmers break down problems into smaller and more manageable pieces. By creating procedures and leveraging parameters, programmers generalize processes that can be reused. Procedures allow programmers to draw upon existing code that has already been tested, allowing them to write programs more quickly and with more confidence.
LEARNING OBJECTIVE	AAP-3.F For simulations: Explain how computers can be used to represent real world outcomes or phenomena 1.A Compare simulations with real world context. 1.D
ESSENTIAL KNOWLEDGE	AAP-3.F.1 Simulations are abstractions of more complex objects or phenomena for a specific purpose.	AAP-3.F.2 A simulation is a representation that uses varying sets of values to reflect the changing state of a phenomenon.	AAP-3.F.3 Simulations often mimic real-world events with the purpose of drawing inferences, allowing investigation of a phenomenon without the constraints of the real world.	AAP-3.F.4 The process of developing an abstract simulation involves removing specific details or simplifying functionality.	AAP-3.F.5 Simulations can contain bias derived from the choices of real-world elements that were included or excluded.	AAP-3.F.6 Simulations are most useful when real-world events are impractical for experiments (e.g., too big, too small, too fast, too slow, too expensive, or too dangerous).	AAP-3.F.7 Simulations facilitate the formulation and refinement of hypotheses related to the objects or phenomena under consideration.	AAP-3.F.8 Random number generators can be used to simulate the variability that exists in the real world.

3.17 Algorithmic Efficiency

TOPIC	3.17 Algorithmic Efficiency
ENDURING UNDERSTANDING	AAP-4 There exist problems that computers cannot solve, and even when a computer can solve a problem, it may not be able to do so in a reasonable amount of time.
LEARNING OBJECTIVE	AAP-4.A For determining the efficiency of an algorithm: Explain the difference between algorithms that run in a reasonable amount of time and those that do not. 1.D Identify situations where a heuristic solution may be more appropriate. 1.D
ESSENTIAL KNOWLEDGE	AAP-4.A.1 A problem is a general description of a task that can (or cannot) be solved algorithmically. An instance of a problem also includes specific input. For example, sorting is a problem; sorting the list (2,3,1,7) is an instance of the problem.	AAP-4.A.2 A decision problem is a problem with a yes/no answer (e.g., is there a path from A to B?). An optimization problem is a problem with the goal of finding the best solution among many (e.g., what is the shortest path from A to B?).	AAP-4.A.3 Efficiency is an estimation of the amount of computational resources used by an algorithm. Efficiency is typically expressed as a function of the size of the input. (no Big-O needed)	AAP-4.A.4 An algorithm's efficiency is determined through formal or mathematical reasoning.	AAP-4.A.5 An algorithm's efficiency can be informally measured by determining the number of times a statement or group of statements executes.	AAP-4.A.6 Different correct algorithms for the same problem can have different efficiencies.	AAP-4.A.7 Algorithms with a polynomial efficiency or slower (constant, linear, square, cube, etc.) are said to run in a reasonable amount of time. Algorithms with exponential or factorial efficiencies are examples of algorithms that run in an unreasonable amount of time.	AAP-4.A.8 Some problems cannot be solved in a reasonable amount of time because there is no efficient algorithm for solving them. In these cases, approximate solutions are sought.	AAP-4.A.9 A heuristic is an approach to a problem that produces a solution that is not guaranteed to be optimal but may be used when techniques that are guaranteed to always find an optimal solution are impractical.

3.18 Undecidable Problems

TOPIC	3.18 Undecidable Problems
ENDURING UNDERSTANDING	AAP-4 There exist problems that computers cannot solve, and even when a computer can solve a problem, it may not be able to do so in a reasonable amount of time.
LEARNING OBJECTIVE	AAP-4.B Explain the existence of undecidable problems in computer science.‚ 1.A
ESSENTIAL KNOWLEDGE	AAP-4.B.1 A decidable problem is a decision problem for which an algorithm can be written to produce a correct output for all inputs (e.g., Is the number even?).	AAP-4.B.2 An undecidable problem is one for which no algorithm can be constructed that is always capable of providing a correct yes-or-no answer.	AAP-4.B.3 An undecidable problem may have some instances that have an algorithmic solution, but there is no algorithmic solution that could solve all instances of the problem.

Activities

Sample Activities	Predict and compare Provide students with a list of expressions with assignments. Ask them to predict the value of each variable after the assignment and then compare their answers to the output produced when these statements are put into a program.
	Using manipulatives When learning about conditionals, take a printout of a simple conditional statement and cut it into multiple sections. As students enter the classroom, hand them an envelope full of the paper strips, and ask them to reassemble the conditional in the proper order.
	Marking the text Provide students with program code that draws a square of side length 10 and a separate set of program code that uses side length 100. Ask students to mark up the sets of code to identify where they are different and to create a generalization by using parameters. Ask them to write a procedure that uses parameters to draw a square of any size.
	Think-pair-share Have students work in pairs to consider what factors would be the most important to prioritize in writing an algorithm to build the perfect master schedule for the school. Some considerations may include maximum class size, student preferences, and teacher availability. Have the pairs discuss and then report their results. Finally, discuss as a class how such programs may have to settle for a good enough solution when an exact solution may not be possible in a reasonable amount of time.

CREATE TASK

Programming is a collaborative and creative process that brings ideas to life through the development of software. In the Create performance task, you will design and implement a program that might solve a problem, enable innovation, explore personal interests, or express creativity. Your submission must include the elements listed in the Submission Requirements section below.

You are allowed to collaborate with your partner(s) on the development of the program only. The written response and the video that you submit for this performance task must be completed individually, without any collaboration with your partner(s) or anyone else. You can develop the code segments used in the written responses (parts 3b and 3c) with your partner(s) or on your own during the administration of the performance task.

Please note that once this performance task has been assigned as an assessment for submission to College Board, you are expected to complete the task without assistance from anyone except for your partner(s) and then only when developing the program code. You must follow the Guidelines for Completing the Create Performance Task section below.

Please Visit Collegeboard for up to date information on the create task.

UNIT 4: Computer Systems and Networks

Overview

AP EXAM WEIGHTING	11–16%
CLASS PERIODS	~14
OVERVIEW	The Internet is a network that most students use on a regular basis to look up information, to socialize with friends, and in many cases to complete their school work. In this big idea, students will learn how computer systems and networks, primarily the Internet, work. Students will learn about how information is transmitted on the Internet and about the safeguards that have been put in place to keep this system from breaking down. In addition, students will learn the effect that dividing tasks across multiple computing devices can have on the speed at which processes can occur. This big idea is often taught in conjunction with Big Idea 5: Impact of Computing.

4.1 The Internet

TOPIC	4.1 The Internet
ENDURING UNDERSTANDING	CSN-1 Computer systems and networks facilitate the transfer of data.
LEARNING OBJECTIVE	CSN-1.A Explain how computing devices work together in a network. 5.A	CSN-1.B Explain how the Internet works.‚ 5.A	CSN-1.C Explain how data are sent through the Internet via packets. 5.A	CSN-1.D Describe the differences between the Internet and the World Wide Web.‚ 5.A
ESSENTIAL KNOWLEDGE	CSN-1.A.1 A computing device is a physical artifact that can run a program. Some examples include computers, tablets, servers, routers, and smart sensors. CSN-1.A.2 A computing system is a group of computing devices and programs working together for a common purpose. CSN-1.A.3 A computer network is a group of interconnected computing devices capable of sending or receiving data. CSN-1.A.4 A computer network is a type of computing system. CSN-1.A.5 A path between two computing devices on a computer network (a sender and a receiver) is a sequence of directly connected computing devices that begins at the sender and ends at the receiver. CSN-1.A.6 Routing is the process of finding a path from sender to receiver	CSN-1.A.7 The bandwidth of a computer network is the maximum amount of data that can be sent in a fixed amount of time. CSN-1.A.8 Bandwidth is usually measured in bits per second. CSN-1.B.1 The Internet is a computer network consisting of interconnected networks that use standardized, open (nonproprietary) communication protocols. CSN-1.B.2 Access to the Internet depends on the ability to connect a computing device to an Internetconnected device. CSN-1.B.3 A protocol is an agreed-upon set of rules that specify the behavior of a system. CSN-1.B.4 The protocols used in the Internet are open, which allows users to easily connect additional computing devices to the Internet. CSN-1.B.5 Routing on the Internet is usually dynamic; it is not specified in advance. CSN-1.B.6 The scalability of a system is the capacity for the system to change in size and scale to meet new demands. CSN-1.B.7 The Internet was designed to be scalable	CSN-1.C.1 Information is passed through the Internet as a data stream. Data streams contain chunks of data, which are encapsulated in packets. CSN-1.C.2 Packets contain a chunk of data and metadata used for routing the packet between the origin and the destination on the Internet, as well as for data reassembly. CSN-1.C.3 Packets may arrive at the destination in order, out of order, or not at all. CSN-1.C.4 IP, TCP, and UDP are common protocols used on the Internet. CSN-1.D.1 The World Wide Web is a system of linked pages, programs, and files. CSN-1.D.2 HTTP is a protocol used by the World Wide Web. CSN-1.D.3 The World Wide Web uses the Internet.

4.2 Fault Tolerance

TOPIC	4.2 Fault Tolerance
ENDURING UNDERSTANDING	CSN-1 Computer systems and networks facilitate the transfer of data.
LEARNING OBJECTIVE	CSN-1.E For fault-tolerant systems, like the Internet: Describe the benefits of fault tolerance.‚ 1.D Explain how a given system is fault-tolerant.‚ 5.A Identify vulnerabilities to failure in a system.‚ 1.D
ESSENTIAL KNOWLEDGE	CSN-1.E.1 The Internet has been engineered to be faulttolerant, with abstractions for routing and transmitting data.	CSN-1.E.2 Redundancy is the inclusion of extra components that can be used to mitigate failure of a system if other components fail.	CSN-1.E.3 One way to accomplish network redundancy is by having more than one path between any two connected devices.	CSN-1.E.4 If a particular device or connection on the Internet fails, subsequent data will be sent via a different route, if possible.	CSN-1.E.5 When a system can support failures and still continue to function, it is called fault-tolerant. This is important because elements of complex systems fail at unexpected times, often in groups, and fault tolerance allows users to continue to use the network.	CSN-1.E.6 Redundancy within a system often requires additional resources but can provide the benefit of fault tolerance.	CSN-1.E.7 The redundancy of routing options between two points increases the reliability of the Internet and helps it scale to more devices and more people.

4.3 Parallel and Distributed Computing

TOPIC	4.3Parallel and Distributed Computing
ENDURING UNDERSTANDING	CSN-2 Parallel and distributed computing leverage multiple computers to more quickly solve complex problems or process large data sets.
LEARNING OBJECTIVE	CSN-2.A For sequential, parallel, and distributed computing: Compare problem solutions.‚ 1.D Determine the efficiency of solutions.‚ 1.D							CSN-2.B Describe benefits and challenges of parallel and distributed computing.‚ 1.D
ESSENTIAL KNOWLEDGE	CSN-2.A.1 Sequential computing is a computational model in which operations are performed in order one at a time.	CSN-2.A.2 Parallel computing is a computational model where the program is broken into multiple smaller sequential computing operations, some of which are performed simultaneously.	CSN-2.A.3 Distributed computing is a computational model in which multiple devices are used to run a program.	CSN-2.A.4 Comparing efficiency of solutions can be done by comparing the time it takes them to perform the same task.	CSN-2.A.5 A sequential solution takes as long as the sum of all of its steps.	CSN-2.A.6 A parallel computing solution takes as long as its sequential tasks plus the longest of its parallel tasks.	CSN-2.A.7 The speedup of a parallel solution is measured in the time it took to complete the task sequentially divided by the time it took to complete the task when done in parallel.	CSN-2.B.1 Parallel computing consists of a parallel portion and a sequential portion.	CSN-2.B.2 Solutions that use parallel computing can scale more effectively than solutions that use sequential computing.	CSN-2.B.3 Distributed computing allows problems to be solved that could not be solved on a single computer because of either the processing time or storage needs involved	CSN-2.B.4 Distributed computing allows much larger problems to be solved quicker than they could be solved using a single computer.	CSN-2.B.5 When increasing the use of parallel computing in a solution, the efficiency of the solution is still limited by the sequential portion. This means that at some point, adding parallel portions will no longer meaningfully increase efficiency.

Activities

Sample Activities

Journaling Ask students to read about the Internet and packet switching in Blown to Bits. Pose several prompts related to the Internet, such as the following, and have students add their answers to their journals: How is the Internet like the US Post Office? Explain the difference between circuit switching and packet switching. Ask students to use what they learned from reading to make a drawing showing how they think an email travels from one place to another.

Predict and compare When introducing parallel and distributed computing, present students with a set of processes and several distributed models. Ask students to compare the models and predict which one is the most efficient, least efficient, or equivalent to other models in the set. Then show students how to determine the efficiency of each model to check if their predictions were correct.

UNIT 5: Impact of Computing

AP EXAM WEIGHTING	21–26%
CLASS PERIODS	~27
OVERVIEW	The creation of computer programs can have extensive impacts, some unintended, on societies, economies, and cultures. In this big idea, students explore these effects, the legal and ethical concerns that come with programs, and the responsibilities of programmers. When using computing innovations and transmitting information via the Internet, students should be aware of the risk of sharing personal identifiable information about themselves, such as their age or address, and actively take steps to keep this information safe. This big idea can be integrated throughout the course and works well with the Creative Development, Data, and Computing Systems and Networks big ideas.

5.1 Beneficial and Harmful Effects

TOPIC	5.1 Beneficial and Harmful Effects
ENDURING UNDERSTANDING	IOC-1 While computing innovations are typically designed to achieve a specific purpose, they may have unintended consequences.
LEARNING OBJECTIVE	IOC-1.A Explain how an effect of a computing innovation can be both beneficial and harmful. 5.C					IOC-1.B Explain how a computing innovation can have an impact beyond its intended purpose. 5.C
ESSENTIAL KNOWLEDGE	IOC-1.A.1 People create computing innovations.	IOC-1.A.2 The way people complete tasks often changes to incorporate new computing innovations.	IOC-1.A.3 Not every effect of a computing innovation is anticipated in advance.	IOC-1.A.4 A single effect can be viewed as both beneficial and harmful by different people, or even by the same person.	IOC-1.A.5 Advances in computing have generated and increased creativity in other fields, such as medicine, engineering, communications, and the arts.	IOC-1.B.1 Computing innovations can be used in ways that their creators had not originally intended: The World Wide Web was originally intended only for rapid and easy exchange of information within the scientific community. Targeted advertising is used to help businesses, but it can be misused at both individual and aggregate levels. Machine learning and data mining have enabled innovation in medicine, business, and science, but information discovered in this way has also been used to discriminate against groups of individuals.	IOC-1.B.2 Some of the ways computing innovations can be used may have a harmful impact on society, the economy, or culture.	IOC-1.B.3 Responsible programmers try to consider the unintended ways their computing innovations can be used and the potential beneficial and harmful effects of these new uses.	IOC-1.B.4 It is not possible for a programmer to consider all the ways a computing innovation can be used.	IOC-1.B.5 Computing innovations have often had unintended beneficial effects by leading to advances in other fields.	IOC-1.B.6 Rapid sharing of a program or running a program with a large number of users can result in significant impacts beyond the intended purpose or control of the programmer.

5.2 Constructors

TOPIC	5.2 Digital Divide
ENDURING UNDERSTANDING	IOC-1 While computing innovations are typically designed to achieve a specific purpose, they may have unintended consequences.
LEARNING OBJECTIVE	IOC-1.C Describe issues that contribute to the digital divide. 5.C
ESSENTIAL KNOWLEDGE	IOC-1.C.1 Internet access varies between socioeconomic, geographic, and demographic characteristics, as well as between countries.	IOC-1.C.2 The digital divide refers to differing access to computing devices and the Internet, based on socioeconomic, geographic, or demographic characteristics.	IOC-1.C.3 The digital divide can affect both groups and individuals.	IOC-1.C.4 The digital divide raises issues of equity, access, and influence, both globally and locally	IOC-1.C.5 The digital divide is affected by the actions of individuals, organizations, and governments.

5.3 Computing Bias

TOPIC	5.3 Documentation with Comments
ENDURING UNDERSTANDING	IOC-1 While computing innovations are typically designed to achieve a specific purpose, they may have unintended consequences.
LEARNING OBJECTIVE	IOC-1.D Explain how bias exists in computing innovations.‚ 5.E
ESSENTIAL KNOWLEDGE	IOC-1.D.1 Computing innovations can reflect existing human biases because of biases written into the algorithms or biases in the data used by the innovation.	IOC-1.D.2 Programmers should take action to reduce bias in algorithms used for computing innovations as a way of combating existing human biases.	IOC-1.D.3 Biases can be embedded at all levels of software development.

5.4 Crowdsourcing

TOPIC	5.4 Crowdsourcing
ENDURING UNDERSTANDING	IOC-1 While computing innovations are typically designed to achieve a specific purpose, they may have unintended consequences.
LEARNING OBJECTIVE	IOC-1.E Explain how people participate in problem-solving processes at scale. 1.C
ESSENTIAL KNOWLEDGE	IOC-1.E.1 Widespread access to information and public data facilitates the identification of problems, development of solutions, and dissemination of results.	IOC-1.E.2 Science has been affected by using distributed and citizen science to solve scientific problems.	IOC-1.E.3 Citizen science is scientific research conducted in whole or part by distributed individuals, many of whom may not be scientists, who contribute relevant data to research using their own computing devices.	IOC-1.E.4 Crowdsourcing is the practice of obtaining input or information from a large number of people via the Internet.	IOC-1.E.5 Human capabilities can be enhanced by collaboration via computing.	IOC-1.E.6 Crowdsourcing offers new models for collaboration, such as connecting businesses or social causes with funding.

5.5 Legal and Ethical Concerns

TOPIC	5.5 Legal and Ethical Concerns
ENDURING UNDERSTANDING	IOC-1 While computing innovations are typically designed to achieve a specific purpose, they may have unintended consequences.
LEARNING OBJECTIVE	IOC-1.F Explain how the use of computing can raise legal and ethical concerns., 5.E
ESSENTIAL KNOWLEDGE	IOC-1.F.1 Material created on a computer is the intellectual property of the creator or an organization. IOC-1.F.2 Ease of access and distribution of digitized information raises intellectual property concerns regarding ownership, value, and use. IOC-1.F.3 Measures should be taken to safeguard intellectual property IOC-1.F.4 The use of material created by someone else without permission and presented as one's own is plagiarism and may have legal consequences. IOC-1.F.5 Some examples of legal ways to use materials created by someone else include: Creative Commons a public copyright license that enables the free distribution of an otherwise copyrighted work. This is used when the content creator wants to give others the right to share, use, and build upon the work they have created. open source programs that are made freely available and may be redistributed and modified open access online research output free of any and all restrictions on access and free of many restrictions on use, such as copyright or license restrictions IOC-1.F.6 The use of material created by someone other than you should always be cited. IOC-1.F.7 Creative Commons, open source, and open access have enabled broad access to digital information. IOC-1.F.8 As with any technology or medium, using computing to harm individuals or groups of people raises legal and ethical concerns. IOC-1.F.9 Computing can play a role in social and political issues, which in turn often raises legal and ethical concerns IOC-1.F.10 The digital divide raises ethical concerns around computing. IOC-1.F.11 Computing innovations can raise legal and ethical concerns. Some examples of these include: the development of software that allows access to digital media downloads and streaming the development of algorithms that include bias the existence of computing devices that collect and analyze data by continuously monitoring activities

5.6 Safe Computing

TOPIC	5.6 Safe Computing
ENDURING UNDERSTANDING	IOC-2 The use of computing innovations may involve risks to personal safety and identity.
LEARNING OBJECTIVE	IOC-2.A Describe the risks to privacy from collecting and storing personal data on a computer system.‚ 5.D	IOC-2.B Explain how computing resources can be protected and can be misused.‚ 5.E	IOC-2.C Explain how unauthorized access to computing resources is gained.‚ 5.E
ESSENTIAL KNOWLEDGE	IOC-2.A.1 Personally identifiable information (PII) is information about an individual that identifies, links, relates, or describes them. Examples of PII include: Social Security number age race phone number(s) medical information financial information biometric data IOC-2.A.2 Search engines can record and maintain a history of searches made by users. IOC-2.A.3 Websites can record and maintain a history of individuals who have viewed their pages. IOC-2.A.4 Devices, websites, and networks can collect information about a user's location. IOC-2.A.5 Technology enables the collection, use, and exploitation of information about, by, and for individuals, groups, and institutions. IOC-2.A.6 Search engines can use search history to suggest websites or for targeted marketing. IOC-2.A.7 Disparate personal data, such as geolocation, cookies, and browsing history, can be aggregated to create knowledge about an individual. IOC-2.A.8 PII and other information placed online can be used to enhance a user's online experiences. IOC-2.A.9 PII stored online can be used to simplify making online purchases. IOC-2.A.10 Commercial and governmental curation of information may be exploited if privacy and other protections are ignored. IOC-2.A.11 Information placed online can be used in ways that were not intended and that may have a harmful impact. For example, an email message may be forwarded, tweets can be retweeted, and social media posts can be viewed by potential employers. IOC-2.A.12 PII can be used to stalk or steal the identity of a person or to aid in the planning of other criminal acts IOC-2.A.13 Once information is placed online, it is difficult to delete. IOC-2.A.14 Programs can collect your location and record where you have been, how you got there, and how long you were at a given location. IOC-2.A.15 Information posted to social media services can be used by others. Combining information posted on social media and other sources can be used to deduce private information about you.	IOC-2.B.1 Authentication measures protect devices and information from unauthorized access. Examples of authentication measures include strong passwords and multifactor authentication. IOC-2.B.2 A strong password is something that is easy for a user to remember but would be difficult for someone else to guess based on knowledge of that user. IOC-2.B.3 Multifactor authentication is a method of computer access control in which a user is only granted access after successfully presenting several separate pieces of evidence to an authentication mechanism, typically in at least two of the following categories: knowledge (something they know), possession (something they have), and inherence (something they are). IOC-2.B.4 Multifactor authentication requires at least two steps to unlock protected information; each step adds a new layer of security that must be broken to gain unauthorized access. IOC-2.B.5 Encryption is the process of encoding data to prevent unauthorized access. Decryption is the process of decoding the data. Two common encryption approaches are: Symmetric key encryption involves one key for both encryption and decryption. Public key encryption pairs a public key for encryption and a private key for decryption. The sender does not need the receiver's private key to encrypt a message, but the receiver's private key is required to decrypt the message. IOC-2.B.6 Certificate authorities issue digital certificates that validate the ownership of encryption keys used in secure communications and are based on a trust model. IOC-2.B.7 Computer virus and malware scanning software can help protect a computing system against infection. IOC-2.B.8 A computer virus is a malicious program that can copy itself and gain access to a computer in an unauthorized way. Computer viruses often attach themselves to legitimate programs and start running independently on a computer. IOC-2.B.9 Malware is software intended to damage a computing system or to take partial control over its operation. IOC-2.B.10 All real-world systems have errors or design flaws that can be exploited to compromise them. Regular software updates help fix errors that could compromise a computing system. IOC-2.B.11 Users can control the permissions programs have for collecting user information. Users should review the permission settings of programs to protect their privacy.	IOC-2.C.1 Phishing is a technique that attempts to trick a user into providing personal information. That personal information can then be used to access sensitive online resources, such as bank accounts and emails. IOC-2.C.2 Keylogging is the use of a program to record every keystroke made by a computer user in order to gain fraudulent access to passwords and other confidential information. IOC-2.C.3 Data sent over public networks can be intercepted, analyzed, and modified. One way that this can happen is through a rogue access point. IOC-2.C.4 A rogue access point is a wireless access point that gives unauthorized access to secure networks. IOC-2.C.5 A malicious link can be disguised on a web page or in an email message. IOC-2.C.6 Unsolicited emails, attachments, links, and forms in emails can be used to compromise the security of a computing system. These can come from unknown senders or from known senders whose security has been compromised. IOC-2.C.7 Untrustworthy (often free) downloads from freeware or shareware sites can contain malware.

Activities

Sample Activities

Marking the text Provide students with an article that highlights both beneficial and harmful effects of a specific computing innovation, and have them mark which effects are beneficial and which are harmful. For each effect the students mark as harmful, have them add notes about whether they think these effects should have been anticipated in advance. For each effect the students mark as beneficial, have the students make notes indicating if they think these benefits were intended or unintended.

Kinesthetic learning In small groups, have students create and act out a play or a scene involving privacy and security risks, especially when it comes to personally identifiable information (PII) and the impact of collecting such data. Sample topics might include not recognizing a phishing email, being careless with passwords, downloading a virus accidentally, or not being aware of a search history being kept on a computer. Students could extend their play to include best practices or ways to stay safer when using computing innovations.

HTML/CSS

Overview

CLASS PERIODS	~30
OVERVIEW	The past decade has connected people online to a once fictional level of communication. The World Wide Web is a front end to many of our online lives. Learning how to design and put together websites is a skill that all computer users may benifit from. HTML allows developers to write websites and CSS allows developers write beautiful websites.
Essential Questions	HTML is a gateway to more abstract and powerful computer programming languages. CSS is a great way to create an abstract but powerful way to make websites beautiful

HTML

Learning Objectives (Students will be able to ...)	Introduction • How the web works • Learning from other pages	Structure • Understanding structure • Learning about markup • Tags and elements	Text • Headings and paragraphs • Bold, italic, emphasis • Structural and semantic markup	Lists • Numbered lists • Bullet lists • Definition lists	Links • Creating links between pages • Linking to other sites • Email links	Images • How to add images to pages • Choosing the right format • Optimizing images for the web	Tables • How to create tables • What information suits tables • How to represent complex data in tables	Forms • How to collect information from visitors • Different kinds of form controls • New HTML5 form controls	Extra Markup • Specifying different versions of HTML • Identifying and grouping elements • Comments, meta information and iframes
Summary	• Brackets is the text editor we use • Github is where we store our websites	•HTML pages are text documents. •HTML uses tags (characters that sit inside angled brackets) to give the information they surround special meaning. •Tags are often referred to as elements. •Tags usually come in pairs. The opening tag denotes the start of a piece of content; the closing tag denotes the end. •Opening tags can carry attributes, which tell us more about the content of that element. •Attributes require a name and a value. •To learn HTML you need to know what tags are available for you to use, what they do, and where they can go.	•HTML elements are used to describe the structure of the page (e.g. headings, subheadings, paragraphs). •They also provide semantic information (e.g. where emphasis should be placed, the de nition of any acronyms used, when given text is a quotation).	•There are three types of HTML lists: ordered, unordered, and definition. •Ordered lists use numbers. •Unordered lists use bullets. •Definition lists are used to de ne terminology. •Lists can be nested inside one another.	•Links are created using the <a> element. •The <a> element uses the href attribute to indicate the page you are linking to. •If you are linking to a page within your own site, it is best to use relative links rather than quali ed URLs. •You can create links to open email programs with an email address in the "to" eld. •You can use the id attribute to target elements within a page that can be linked to.	•The <img> element is used to add images to a web page. •You must always specify a src attribute to indicate the source of an image and an alt attribute to describe the content of an image. •You should save images at the size you will be using them on the web page and in the appropriate format. •Photographs are best saved as JPEGs; illustrations or logos that use at colors are better saved as GIFs.	•The <table> element is used to add tables to a web page. •A table is drawn out row by row. Each row is created with the <tr> element. •Inside each row there are a number of cells represented by the <td> element (or <th> if it is a header). •You can make cells of a table span more than one row or column using the rowspan and colspan attributes. •For long tables you can split the table into a <thead>, <tbody>, and <tfoot>.	•Whenever you want to collect information from visitors you will need a form, which lives inside a <form> element. •Information from a form is sent in name/value pairs. •Each form control is given a name, and the text the user types in or the values of the options they select are sent to the server. •HTML5 introduces new form elements which make it easier for visitors to ll in forms.	•DOCTYPES tell browsers which version of HTML you are using. •You can add comments to your code between the <!-- and --> markers. •The id and class attributes allow you to identify particular elements. •The <div> and <span> elements allow you to group block-level and inline elements together. •<iframes> cut windows into your web pages through which other pages can be displayed. •The <meta> tag allows you to supply all kinds of information about your web page. •Escape characters are used to include special characters in your pages such as <, >, and ©.
Tags		doctypes <!-- comments --> <head> <body> <title>	<h1><h2><h3><h4><h5><h6><p><b><i><sup><sub><br><hr><strong><em><blockquote><q><abbr><cite><dfn><address><ins><del><s>	<ol><li><ul><li><dl><dt><dd>	<a> [mailto:] [target]	<img> [scr][alt][title][height][width][align]	<table><tr><td><th><thead><tbody><tfoot>	<form>[action][method][id]<input>[type="..."][name][size][maxlength]<textarea><select><option><button><fieldset><legend>	doctypes<!-- comments --> <div><span><iframe><meta>
Assignments	Setup a github account	Write Hello World, tell me who you are. Tell me 3 favorite foods. 3 favorite bands. 3 favorite classes. And give me directions on how to make your favorite meal (get the instructions online, at the bottom of your page put the website you get the instructions from.	Put headings above each of your favorite things from the last assignment. Use the line break tag to seperate your text. Use the del tag to "cross off" one of your favorite things and replace it with a strong OR emphasis tag. Use the Horizontal Rule tag, make a new heading and call it math, then using superscript type out the pythagreon theorm, under the pythagreon theorm tell me if you like math or not. Use subscript and make your own citation with your food instructions.	Make your food list an ordered list. Make your other lists unordered lists.	Make a hyper-link to the food instructions. Hyper-link many of your other list items to relevant websites. Put a hyperlink to email you. This may be a fake email address.	Put a picture of yourself, or a picture that represents you on the page. This picture must be local. Put remote pictures to your favorites. When the picture is clicked on you must link to the origional page.	Make a new web page with your roster in a table. Link your two web pages together.	Make a new feedback form for your website. It should be linked from your origional site. You must use the radio buttons, checkboxes, text boxes, and drop down. Post to: <form action= "http://www.phillycomputerscience.com/post/formreturn.php" method="post">	Add div and span Tags to your webpage. Give the tags name and id elements.

CSS

Learning Objectives (Students will be able to ...)	Introducing CSS • What CSS does • How CSS works • Rules, properties, and values	Colors • How to specify colors • Color terminology and contrast • Background color	Text • Size and typeface of text • Bold, italics, capitals, underlines • Spacing between lines, words, and letters	Boxes • Controlling size of boxes • Box model for borders, margin and padding • Displaying and hiding boxes	Lists, tables and Forms • Specifying bullet point styles • Adding borders and backgrounds to tables • Changing the appearance of form elements	Layout • Controlling the position of elements • Creating site layouts • Designing for different sized screens	Images • Controlling size of images in CSS • Aligning images in CSS • Adding background images	HTML 5 Layout • HTML5 layout elements • How old browsers understand new elements • Styling HTML5 layout elements with CSS	Process & Design • How to approach building a site • Understanding your audience and their needs • How to present information visitors want to see	Practical Information • Search engine optimization • Using analytics to understand visitors • Putting your site on the web
Summary	•CSS treats each HTML element as if it appears inside its own box and uses rules to indicate how that element should look. •Rules are made up of selectors (that specify the elements the rule applies to) and declarations (that indicate what these elements should look like). •Different types of selectors allow you to target your rules at different elements. •Declarations are made up of two parts: the properties of the element that you want to change, and the values of those properties. For example, the font-family property sets the choice of font, and the value arial speci es Arial as the preferred typeface. •CSS rules usually appear in a separate document, although they may appear within an HTML page.	•Color not only brings your site to life, but also helps convey the mood and evokes reactions. •There are three ways to specify colors in CSS: RGB values, hex codes, and color names. •Color pickers can help you and the color you want. •It is important to ensure that there is enough contrast between any text and the background color (otherwise people will not be able to read your content). •CSS3 has introduced an extra value for RGB colors to indicate opacity. It is known as RGBA. •CSS3 also allows you to specify colors as HSL values, with an optional opacity value. It is known as HSLA.	•There are properties to control the choice of font, size, weight, style, and spacing. •There is a limited choice of fonts that you can assume most people will have installed. •If you want to use a wider range of typefaces there are several options, but you need to have the right license to use them. •You can control the space between lines of text, individual letters, and words. Text can also be aligned to the left, right, center, or justi ed. It can also be indented. •You can use pseudo-classes to change the style of an element when a user hovers over or clicks on text, or when they have visited a link.	•CSS treats each HTML element as if it has its own box. •You can use CSS to control the dimensions of a box. •You can also control the borders, margin and padding for each box with CSS. •It is possible to hide elements using the display and visibility properties. •Block-level boxes can be made into inline boxes, and inline boxes made into block-level boxes. •Legibility can be improved by controlling the width of boxes containing text and the leading. •CSS3 has introduced the ability to create image borders and rounded borders.	•In addition to the CSS properties covered in other chapters which work with the contents of all elements, there are several others that are speci cally used to control the appearance of lists, tables, and forms. •List markers can be given different appearances using the list-style-type and list-style image properties. •Table cells can have different borders and spacing in different browsers, but there are properties you can use to control them and make them more consistent. •Forms are easier to use if the form controls are vertically aligned using CSS. •Forms bene t from styles that make them feel more interactive.	•<div> elements are often used as containing elements to group together sections of a page. •Browsers display pages in normal ow unless you specify relative, absolute, or xed positioning. •The float property moves content to the left or right of the page and can be used to create multi-column layouts. (Floated items require a de ned width.) •Pages can be xed width or liquid (stretchy) layouts. •Designers keep pages within 960-1000 pixels wide, and indicate what the site is about within the top 600 pixels (to demonstrate its relevance without scrolling). •Grids help create professional and exible designs. X •CSS Frameworks provide rules for common tasks. X You can include multiple CSS les in one page.	•You can specify the dimensions of images using CSS. This is very helpful when you use the same sized images on several pages of your site. •Images can be aligned both horizontally and vertically using CSS. •You can use a background image behind the box created by any element on a page. •Background images can appear just once or be repeated across the background of the box. •You can create image rollover effects by moving the background position of an image. •To reduce the number of images your browser has to load, you can create image sprites.	•The new HTML5 elements indicate the purpose of different parts of a web page and help to describe its structure. •The new elements provide clearer code (compared with using multiple <div> elements). •Older browsers that do not understand HTML5 elements need to be told which elements are block-level elements. •To make HTML5 elements work in Internet Explorer 8 (and older versions of IE), extra JavaScript is needed, which is available free from Google.	•It's important to understand who your target audience is, why they would come to your site, what information they want to nd and when they are likely to return. •Site maps allow you to plan the structure of a site. •Wireframes allow you to organize the information that will need to go on each page. •Design is about communication. Visual hierarchy helps visitors understand what you are trying to tell them. •You can differentiate between pieces of information using size, color, and style. •You can use grouping and similarity to help simplify the information you present.	•Search engine optimization helps visitors nd your sites when using search engines. •Analytics tools such as Google •Analytics allow you to see how many people visit your site, how they nd it, and what they do when they get there. •To put your site on the web, you will need to obtain a domain name and web hosting. •FTP programs allow you to transfer les from your local computer to your web server. •Many companies provide platforms for blogging, email newsletters, e-commerce and other popular website tools (to save you writing them from scratch).
Assignments	Link Your CSS file to your website	change font and background colors on your website.	Change fonts useing default and google fonts. Change font sizes	Change the width and height of your HTML elements. Add borders margins and padding. Make a new page with 50 div tags. Make css art.	Make your form beautiful! Make your roster beautiful.	Make a new html page with a poem. Using hover and graphics make your poem beautiful and interactive.		CSS Grid. Make a newspaper layout.	Make a nice menu.	Resize your window big and small. Ajust your page so that it always looks great. (400px-1200px)

Applied Technology & Safety

Overview

CLASS PERIODS	~20
OVERVIEW	SDP is a Google School District. Google much like Apple, Microsoft and a host of other companies product lines allow their users to get much of their computer tasks done. Most packages include web browsers, word processors, spreadsheets, presentation tools, email, cloud storage, and many other tools. We will explore the google tools most High School students use today as well as look into alternative options and explore into other less known tools.
Essential Questions	How can we navigate a healthy and happy lifestyle while balancing our digital and non-digital life.

Topic

Build Healthy Digital Habits

Avoid Online Scams

Evaluate Credibility of Online Sources

Understand Your Digital Footprint

Identify Cyberbullying

Create and Safeguard Passwords

Make Art in Google Sheets

If-Then Adventure Stories

Technology's Role in Current Events

Technology, Ethics, and Security

Technology at Work

Create an Editing Tool with Programming

Introduction to Machine Learning

Overview

In Build Healthy Digital Habits, students explore their digital habits and learn to achieve a balance between screen time and non-connected pursuits. This curriculum encourages students, teachers, families, and guardians to work together to define and balance technology’s role in daily life. Each lesson in this grouping stands alone, so you can choose any lesson out of the three to do with your class, or you can assign all three in sequence or in any order you choose. All students watch the introductory video together, then move on to the lesson you select for them.

In Avoid Online Scams students analyze an online scam to identify warning signs and best practices for identifying and avoiding online scams to stay safe online.

In Evaluate Credibility of Online Sources, students search for an article online and use key questions to evaluate the credibility of its source.

In Understand Your Digital Footprint students will think about the actions they take online and create a visual picture of their digital footprint in Google Sheets.

In Identify Cyberbullying, students will collaborate with classmates in a document to create a plan to recognize and stop cyberbullying.

In Create and Safeguard Passwords, students discover how a hacker guesses passwords using a dictionary attack, then learn how to create and safeguard secure passwords.

In Make Art in Google Sheets, students will use conditional formatting rules to create a personalized pixel art project in Google Sheets.

In If-Then Adventure Stories, students create an interactive story in Google Slides.

In Technology’s Role in Current Events, students research a topic related to technology's role in current events, create a project, and present their findings.

In Technology, Ethics, and Security, students research a topic related to technology safety, create a project, and present their findings.

Students research a topic related to technology's role in the workplace, create a project, and present their findings.

In Create an Editing Tool with Programming, students use Script Editor to create an editing tool that highlights overused words and phrases in a document.

In Introduction to Machine Learning, students explore machine learning in four different ways: 1) by examining simulated data collected from a person driving their car, 2) by collecting data about people’s likes and dislikes in order to create an algorithm to predict future preferences, 3) by exploring how computers learn based on the data they receive, and 4) by considering the benefits and drawbacks of machine learning for real-world decision-making.

GIMP

Overview

CLASS PERIODS	~10
OVERVIEW	The Free & Open Source Image Editor This is the official website of the GNU Image Manipulation Program (GIMP). GIMP is a cross-platform image editor available for GNU/Linux, OS X, Windows and more operating systems. It is free software, you can change its source code and distribute your changes. Whether you are a graphic designer, photographer, illustrator, or scientist, GIMP provides you with sophisticated tools to get your job done. You can further enhance your productivity with GIMP thanks to many customization options and 3rd party plugins.
Essential Questions	How to use creative tools to become more creative and enhance our Computer Science Experience.

Essential Questions:	GIMP - The Free & Open Source Image Editor
Enduring Understandings (Students will understand that ...) OBJECTIVES	GIMP is a cross-platform image editor available for GNU/Linux, OS X, Windows and more operating systems. It is free software, you can change its source code and distribute your changes. Whether you are a graphic designer, photographer, illustrator, or scientist, GIMP provides you with sophisticated tools to get your job done. You can further enhance your productivity with GIMP thanks to many customization options and 3rd party plugins.
Learning Objectives (Students will be able to ...)	Use GIMP for simple graphics needs without having to learn advanced image manipulation methods.	Basic image and layer manipulation techniques.	How to create a circular-shaped image.	An introduction to using layer masks to modify the opacity of a layer.	Detailed conversion tutorial for generating a B&W result from a color image.	Using multiple layer masks to isolate specific tones in your image for editing.	Using high bit depth GIMP’s ‘Colors/Exposure’ operation to add exposure compensation to shadows and midtones while retaining highlight details.
Summary	•Changing the Size (Dimensions) of an Image (Scale) •Changing the Size (Filesize) of a JPEG •Crop an Image •Rotate or Flip an Image	This tutorial is intended to introduce you to a few simple commands, and some concepts in order to create a logo that appears to be floating above a background	There are no circular images. There are only rectangular images. But there can be images where corners are transparent, so that only a circle shows.	Layer masks are a fundamental tool in image manipulations. They allow you to selectively modify the opacity (transparency) of the layer they belong to. This differs from the use of the layer Opacity slider as a mask has the ability to selectively modify the opacity of different areas across a single layer.	Black and White photography is a big topic that deserves entire books devoted to the subject. In this lesson we are going to explore some of the most common methods for converting a color digital image into monochrome in GIMP.	Luminosity masks are basically layer masks that are built around specific tones in an image. They are derived from the image data itself, and focused on a specific range of tonal values. The benefit of using these types of masks is that when targeting tonal ranges the mask itself is self-feathering, helping to avoid problems with blending and hard transitions.	A very common editing problem is how to lighten the shadows and midtones of an image while retaining highlight details, a task sometimes referred to as “shadow recovery” and more generally speaking as “tone mapping”. This step-by-step tutorial shows you how to use high bit depth GIMP’s floating point “Colors/Exposure” operation to add one or more stops of positive exposure compensation to an image’s shadows and midtones while retaining highlight details.
Resources and Materials:	https://www.gimp.org/

javascript

Overview

CLASS PERIODS	~30
OVERVIEW	Once a developer can represent themselves online with HTML and CSS they may then start writing websites that DO things. Javascript is a light yet powerful tool that may introduce students to the world of programming.
ESSENTIAL QUESTIONS	AAP-1 How can we store data in a program to solve problems? AAP-2 What might happen if you completed the steps in your regular morning routine to get ready and go to school in a different order? How might the reordering affect the decisions you make each morning? AAP-3 How do video games group the different actions for a player based on what key is pressed on the keyboard or controller? How do apps group different actions together based on user interaction, such as pressing buttons? AAP-4 What types of problems can be solved more easily with a computer, and what types can be solved more easily without a computer? Why?

Variables and Assignments

TOPIC	3.1 Variables and Assignments
ENDURING UNDERSTANDING	AAP-1 To find specific solutions to generalizable problems, programmers represent and organize data in multiple ways.
LEARNING OBJECTIVE	AAP-1.A Represent a value with a variable. 3.A				AAP-1.B Determine the value of a variable as a result of an assignment.‚ 4.B
ESSENTIAL KNOWLEDGE	AAP-1.A.1 A variable is an abstraction inside a program that can hold a value. Each variable has associated data storage that represents one value at a time, but that value can be a list or other collection that in turn contains multiple values.	AAP-1.A.2 Using meaningful variable names helps with the readability of program code and understanding of what values are represented by the variables.	AAP-1.A.3 Some programming languages provide types to represent data, which are referenced using variables. These types include numbers, Booleans, lists, and strings.	AAP-1.A.4 Some values are better suited to representation using one type of datum rather than another	AAP-1.B.1 The assignment operator allows a program to change the value represented by a variable.	AAP-1.B.2 The exam reference sheet provides the "←" operator to use for assignment. For example: a←expression evaluates expression and then assigns a copy of the result to the variable a.	AAP-1.B.3 The value stored in a variable will be the most recent value assigned. For example: a←1 b←a a←2 display(b) still displays 1.

Data Abstraction

TOPIC	3.2 Data Abstraction
ENDURING UNDERSTANDING	AAP-1 To find specific solutions to generalizable problems, programmers represent and organize data in multiple ways.
LEARNING OBJECTIVE	AAP-1.C Represent a list or string using a variable.‚ 3.A				AAP-1.D For data abstraction: Develop data abstraction using lists to store multiple elements.‚ 3.B Explain how the use of data abstraction manages complexity in program code.‚ 3.C
ESSENTIAL KNOWLEDGE	AAP-1.C.1 A list is an ordered sequence of elements. For example, [value1, value2, value3, ...] describes a list where value1 is the first element, value2 is the second element, value3 is the third element, and so on.	AAP-1.C.2 An element is an individual value in a list that is assigned a unique index.	AAP-1.C.3 An index is a common method for referencing the elements in a list or string using natural numbers.	AAP-1.C.4 A string is an ordered sequence of characters.	AAP-1.D.1 Data abstraction provides a separation between the abstract properties of a data type and the concrete details of its representation.	AAP-1.D.2 Data abstractions manage complexity in programs by giving a collection of data a name without referencing the specific details of the representation.	AAP-1.D.3 Data abstractions can be created using lists.	AAP-1.D.4 Developing a data abstraction to implement in a program can result in a program that is easier to develop and maintain.	AAP-1.D.5 Data abstractions often contain different types of elements.	AAP-1.D.6 The use of lists allows multiple related items to be treated as a single value. Lists are referred to by different names, such as array, depending on the programming language.	AAP-1.D.7 The exam reference sheet provides the notation [value1, value2, value3, ...] to create a list with those values as the first, second, third, and so on items. For example, Text: aList←[value1, value2, value3, ...] creates a new list that contains the values value1, value2, value3, and ... at indices 1, 2, 3, and ... respectively and assigns it to aList. Text: aList ←[] creates a new empty list and assigns it to aList. Text: aList←bList assigns a copy of the list bList to the list aList. For example, if bList contains [20, 40, 60], then aList will also contain [20, 40, 60] after the assignment.	AAP-1.D.8 The exam reference sheet describes a list structure whose index values are 1 through the number of elements in the list, inclusive. For all list operations, if a list index is less than 1 or greater than the length of the list, an error message is produced and the program will terminate.

Mathematical Expressions

TOPIC	3.3 Mathematical Expressions
ENDURING UNDERSTANDING	AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.A Express an algorithm that uses sequencing without using a programming language.‚ 2.A	AAP-2.B Represent a step-by-step algorithmic process using sequential code statements. 2.B	AAP-2.C Evaluate expressions that use arithmetic operators.‚ 4.B
ESSENTIAL KNOWLEDGE	AAP-2.A.1 An algorithm is a finite set of instructions that accomplish a specific task. AAP-2.A.2 Beyond visual and textual programming languages, algorithms can be expressed in a variety of ways, such as natural language, diagrams, and pseudocode. AAP-2.A.3 Algorithms executed by programs are implemented using programming languages. AAP-2.A.4 Every algorithm can be constructed using combinations of sequencing, selection, and iteration.	AAP-2.B.1 Sequencing is the application of each step of an algorithm in the order in which the code statements are given. AAP-2.B.2 A code statement is a part of program code that expresses an action to be carried out. AAP-2.B.3 An expression can consist of a value, a variable, an operator, or a procedure call that returns a value. AAP-2.B.4 Expressions are evaluated to produce a single value. AAP-2.B.5 The evaluation of expressions follows a set order of operations defined by the programming language. AAP-2.B.6 Sequential statements execute in the order they appear in the code segment. AAP-2.B.7 Clarity and readability are important considerations when expressing an algorithm in a programming language.	AAP-2.C.1 Arithmetic operators are part of most programming languages and include addition, subtraction, multiplication, division, and modulus operators. AAP-2.C.2 The exam reference sheet provides a MOD b, which evaluates to the remainder when a is divided by b. Assume that a is an integer greater than or equal to 0 and b is an integer greater than 0. For example, 17 MOD 5 evaluates to 2. AAP-2.C.3 The exam reference sheet provides the arithmetic operators +, -, *, /, and MOD. Text: a + b a - b a * b a / b a MOD b These are used to perform arithmetic on a and b. For example, 17 / 5 evaluates to 3.4. AAP-2.C.4 The order of operations used in mathematics applies when evaluating expressions. The MOD operator has the same precedence as the * and / operators. DAT-2.C.5 Problems of bias are often created by the type or source of data being collected. Bias is not eliminated by simply collecting more data.

Strings

TOPIC	3.4 Strings
ENDURING UNDERSTANDING	AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.D Evaluate expressions that manipulate strings.‚ 4.B
ESSENTIAL KNOWLEDGE	AAP-2.D.1 String concatenation joins together two or more strings end-to-end to make a new string.	AAP-2.D.2 A substring is part of an existing string.

Boolean Expressions

TOPIC	3.5 Boolean Expressions
ENDURING UNDERSTANDING	AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.E For relationships between two variables, expressions, or values: Write expressions using relational operators. 2B Evaluate expressions using relational operators. 4B		AAP-2.F For relationships between Boolean values: Write expressions that use logical operators. 2.B Evaluate expressions that use logic operators.‚ 4.B
ESSENTIAL KNOWLEDGE	AAP-2.E.1 A Boolean value is either true or false.	AAP-2.E.2 The exam reference sheet provides the following relational operators: =, ≠, >, <, ≥, and ≤. Text and Block: a = b a ≠ b a > b a < b a ≤ b a ≥ b These are used to test the relationship between two variables, expressions, or values. A comparison using a relational operator evaluates to a Boolean value. For example, a = b evaluates to true if a and b are equal; otherwise, it evaluates to false.	AAP-2.F.1 The exam reference sheet provides the logical operators NOT, AND, and OR, which evaluate to a Boolean value.	AAP-2.F.2 The exam reference sheet provides Text: NOT condition which evaluates to true if condition is false; otherwise it evaluates to false.	AAP-2.F.3 The exam reference sheet provides Text: condition1 AND condition2 which evaluates to true if both condition1 and condition2 are true; otherwise it evaluates to false.	AAP-2.F.4 The exam reference sheet provides Text: condition1 OR condition2 which evaluates to true if condition1 is true or if condition2 is true or if both condition1 and condition2 are true; otherwise it evaluates to false.	AAP-2.F.5 The operand for a logical operator is either a Boolean expression or a single Boolean value.

Conditionals

TOPIC	3.6 Conditionals
ENDURING UNDERSTANDING	AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.G Express an algorithm that uses selection without using a programming language.‚ 2.A	AAP-2.H For selection: Write conditional statements. 2.B Determine the result of conditional statements. 4.B
ESSENTIAL KNOWLEDGE	AAP-2.G.1 Selection determines which parts of an algorithm are executed based on a condition being true or false.	AAP-2.H.1 Conditional statements, or if-statements, affect the sequential flow of control by executing different statements based on the value of a Boolean expression.	AAP-2.H.2 The exam reference sheet provides Text: IF(condition) { <block of statements> } in which the code in block of statements is executed if the Boolean expression condition evaluates to true; no action is taken if condition evaluates to false.	AAP-2.H.3 The exam reference sheet provides Text: IF(condition) { <first block of statements> } ELSE { <second block of statements> } in which the code in first block of statements is executed if the Boolean expression condition evaluates to true; otherwise, the code in second block of statements is executed.

Nested Conditionals

TOPIC	3.7 Nested Conditionals
ENDURING UNDERSTANDING	ENDURING UNDERSTANDING AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.I For nested selection: Write nested conditional statements. 2.B b. Determine the result of nested conditional statements. 4.B
ESSENTIAL KNOWLEDGE	AAP-2.I.1 Nested conditional statements consist of conditional statements within conditional statements.

Iteration

TOPIC	3.8 Iteration
ENDURING UNDERSTANDING	AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.J Express an algorithm that uses iteration without using a programming language.‚ 2.A	AAP-2.K For iteration: Write iteration statements 2.B Determine the result or side effect of iteration statements. 4.B
ESSENTIAL KNOWLEDGE	AAP-2.J.1 Iteration is a repeating portion of an algorithm. Iteration repeats a specified number of times or until a given condition is met.	AAP-2.K.1 Iteration statements change the sequential flow of control by repeating a set of statements zero or more times, until a stopping condition is met.	AAP-2.K.2 The exam reference sheet provides Text: REPEAT n TIMES { <block of statements> } in which the block of statements is executed n times.	AAP-2.K.3 The exam reference sheet provides Text: REPEAT UNTIL(condition) { <block of statements> } in which the code in block of statements is repeated until the Boolean expression condition evaluates to true.	AAP-2.K.4 In REPEAT UNTIL(condition) iteration, an infinite loop occurs when the ending condition will never evaluate to true.	AAP-2.K.5 In REPEAT UNTIL(condition) iteration, if the conditional evaluates to true initially, the loop body is not executed at all, due to the condition being checked before the loop.

Developing Algorithms

TOPIC	3.9 Developing Algorithms
ENDURING UNDERSTANDING	AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.L Compare multiple algorithms to determine if they yield the same side effect or result.‚ 1.D					AAP-2.M For algorithms: Create algorithms. 2.A Combine and modify existing algroitms. 2.B
ESSENTIAL KNOWLEDGE	AAP-2.L.1 Algorithms can be written in different ways and still accomplish the same tasks.	AAP-2.L.2 Algorithms that appear similar can yield different side effects or results.	AAP-2.L.3 Some conditional statements can be written as equivalent Boolean expressions.	AAP-2.L.4 Some Boolean expressions can be written as equivalent conditional statements.	AAP-2.L.5 Different algorithms can be developed or used to solve the same problem.	AAP-2.M.1 Algorithms can be created from an idea, by combining existing algorithms, or by modifying existing algorithms.	AAP-2.M.2 Knowledge of existing algorithms can help in constructing new ones. Some existing algorithms include: determining the maximum or minimum value of two or more numbers computing the sum or average of two or more numbers identifying if an integer is or is not evenly divisible by another integer determining a robot's path through a maze	AAP-2.M.3 Using existing correct algorithms as building blocks for constructing another algorithm has benefits such as reducing development time, reducing testing, and simplifying the identification of errors.

Lists

TOPIC	3.10 Lists
ENDURING UNDERSTANDING	AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.N For list operations: Write expressions that use list indexing and list procedures.‚ 2.B Evaluate expressions that use list indexing and list procedures.‚ 4.B		AAP-2.O For algorithms involving elements of a list: Write iteration statements that traverse a list. 2.B Determine the result of an algoritms that includes list traversal. 4.B
ESSENTIAL KNOWLEDGE	AAP-2.N.1 The exam reference sheet provides basic operations on lists, including: accessing an element by index Text: aList[i] accesses the element of aList at index i. The first element of aList is at index 1 and is accessed using the notation aList[1]. assigning a value of an element of a list to a variable Text: x←aList [i] assigns the value of aList[i] to the variable x. assigning a value to an element of a list Text: aList[i]←x assigns the value of x to aList[i]. Text: aList[i]←aList[j] assigns the value of aList[j] to aList[i]. inserting elements at a given index Text: INSERT(aList, i, value) shifts to the right any values in aList at indices greater than or equal to i. The length of the list is increased by 1, and value is placed at index i in aList. adding elements to the end of the list Text: APPEND(aList, value) increases the length of aList by 1, and value is placed at the end of aList. removing elements Text: REMOVE(aList, i) removes the item at index i in aList and shifts to the left any values at indices greater than i. The length of aList is decreased by 1. determining the length of a list Text: LENGTH(aList) evaluates to the number of elements currently in aList.	AAP-2.N.2 List procedures are implemented in accordance with the syntax rules of the programming language.	AAP-2.O.1 Traversing a list can be a complete traversal, where all elements in the list are accessed, or a partial traversal, where only a portion of elements are accessed.	AAP-2.O.2 Iteration statements can be used to traverse a list.	AAP-2.O.3 The exam reference sheet provides Text: FOR EACH item IN aList { <block of statements> } The variable item is assigned the value of each element of aList sequentially, in order, from the first element to the last element. The code in block of statements is executed once for each assignment of item.	AAP-2.O.4 Knowledge of existing algorithms that use iteration can help in constructing new algorithms. Some examples of existing algorithms that are often used with lists include: determining a minimum or maximum value in a list computing a sum or average of a list of numbers	AAP-2.O.5 Linear search or sequential search algorithms check each element of a list, in order, until the desired value is found or all elements in the list have been checked.

Binary Search

TOPIC	3.11 Binary Search
ENDURING UNDERSTANDING	AAP-2 The way statements are sequenced and combined in a program determines the computed result. Programs incorporate iteration and selection constructs to represent repetition and make decisions to handle varied input values.
LEARNING OBJECTIVE	AAP-2.P For binary search algorithms: Determine the number of iterations required to find a value in a data set. 1.D Explain the requirements necessary to complete a binary search.‚ 1.A
ESSENTIAL KNOWLEDGE	AAP-2.P.1 The binary search algorithm starts at the middle of a sorted data set of numbers and eliminates half of the data; this process repeat until the desired value is found or all elements have been eliminated.	AAP-2.P.2 Data must be in sorted order to use the binary search algorithm.	AAP-2.P.3 Binary search is often more efficient than sequential/linear search when applied to sorted data.

Calling Procedures

TOPIC	3.12 Calling Procedures
ENDURING UNDERSTANDING	AAP-3 Programmers break down problems into smaller and more manageable pieces. By creating procedures and leveraging parameters, programmers generalize processes that can be reused. Procedures allow programmers to draw upon existing code that has already been tested, allowing them to write programs more quickly and with more confidence.
LEARNING OBJECTIVE	AAP-3.A For procedure calls: Write statements to call procedures 3.B Determine the result or effect of a procedure call 4.B
ESSENTIAL KNOWLEDGE	AAP-3.A.1 A procedure is a named group of programming instructions that may have parameters and return values.	AAP-3.A.2 Procedures are referred to by different names, such as method or function, depending on the programming language.	AAP-3.A.3 Parameters are input variables of a procedure. Arguments specify the values of the parameters when a procedure is called.	AAP-3.A.4 A procedure call interrupts the sequential execution of statements, causing the program to execute the statements within the procedure before continuing. Once the last statement in the procedure (or a return statement) has executed, flow of control is returned to the point immediately following where the procedure was called.	AAP-3.A.5 The exam reference sheet provides procName(arg1, arg2, ...) as a way to call Text: PROCEDURE procName(parameter1, parameter2, ...) { <block of statements> } which takes zero or more arguments; arg1 is assigned to parameter1, arg2 is assigned to parameter2, and so on.	AAP-3.A.6 The exam reference sheet provides the procedure Text: DISPLAY(expression) Block: to display the value of expression, followed by a space.	AAP-3.A.7 The exam reference sheet provides the Text: RETURN(expression) statement, which is used to return the flow of control to the point where the procedure was called and to return the value of expression.	AAP-3.A.8 The exam reference sheet provides result←procName(arg1, arg2, ...) to assign to result the value of the procedure being returned by calling Text: PROCEDURE procName(parameter1, parameter2, ...) { <block of statements> RETURN(expression) }	AAP-3.A.9 The exam reference sheet provides procedure Text: INPUT() which accepts a value from the user and returns the input value.

Developing Procedures

TOPIC	3.13 Developing Procedures
ENDURING UNDERSTANDING	AAP-3 Programmers break down problems into smaller and more manageable pieces. By creating procedures and leveraging parameters, programmers generalize processes that can be reused. Procedures allow programmers to draw upon existing code that has already been tested, allowing them to write programs more quickly and with more confidence
LEARNING OBJECTIVE	AAP-3.B Explain how the use of procedural abstraction manages complexity in a program.‚ 3.C							AAP-3.C Develop procedural abstractions to manage complexity in a program by writing procedures.‚ 3.B
ESSENTIAL KNOWLEDGE	AAP-3.B.1 One common type of abstraction is procedural abstraction, which provides a name for a process and allows a procedure to be used only knowing what it does, not how it does it.	AAP-3.B.2 Procedural abstraction allows a solution to a large problem to be based on the solutions of smaller subproblems. This is accomplished by creating procedures to solve each of the subproblems.	AAP-3.B.3 The subdivision of a computer program into separate subprograms is called modularity.	AAP-3.B.4 A procedural abstraction may extract shared features to generalize functionality instead of duplicating code. This allows for program code reuse, which helps manage complexity.	AAP-3.B.5 Using parameters allows procedures to be generalized, enabling the procedures to be reused with a range of input values or arguments.	AAP-3.B.6 Using procedural abstraction helps improve code readability.	AAP-3.B.7 Using procedural abstraction in a program allows programmers to change the internals of the procedure (to make it faster, more efficient, use less storage, etc.) without needing to notify users of the change as long as what the procedure does is preserved.	AAP-3.C.1 The exam reference sheet provides Text: PROCEDURE procName(parameter1, parameter2, ...) { <block of statements> } which is used to define a procedure that takes zero or more arguments. The procedure contains block of statements.	AAP-3.C.2 The exam reference sheet provides Text: PROCEDURE procName(parameter1, parameter2, ...) { <block of statements> RETURN(expression) } which is used to define a procedure that takes zero or more arguments. The procedure contains block of statements and returns the value of expression. The RETURN statement may appear at any point inside the procedure and causes an immediate return from the procedure back to the calling statement.

Libraries

TOPIC	3.14 Libraries
ENDURING UNDERSTANDING	AAP-3 Programmers break down problems into smaller and more manageable pieces. By creating procedures and leveraging parameters, programmers generalize processes that can be reused. Procedures allow programmers to draw upon existing code that has already been tested, allowing them to write programs more quickly and with more confidence.
LEARNING OBJECTIVE	AAP-3.D Select appropriate libraries or existing code segments to use in creating new programs.‚ 2.B
ESSENTIAL KNOWLEDGE	AAP-3.D.1 A software library contains procedures that may be used in creating new programs.	AAP-3.D.2 Existing code segments can come from internal or external sources, such as libraries or previously written code.	AAP-3.D.3 The use of libraries simplifies the task of creating complex programs.	AAP-3.D.4 Application program interfaces (APIs) are specifications for how the procedures in a library behave and can be used.	AAP-3.D.5 Documentation for an API/library is necessary in understanding the behaviors provided by the API/library and how to use them.

Random Values

TOPIC	3.15 Random Values
ENDURING UNDERSTANDING	AAP-3 Programmers break down problems into smaller and more manageable pieces. By creating procedures and leveraging parameters, programmers generalize processes that can be reused. Procedures allow programmers to draw upon existing code that has already been tested, allowing them to write programs more quickly and with more confidence
LEARNING OBJECTIVE	AAP-3.E For generating random values: Write expressions to generate possible values. 2.B Evaluate expressions to generate possible values. 4.B
ESSENTIAL KNOWLEDGE	AAP-3.E.1 The exam reference sheet provides Text: RANDOM(a, b) which generates and returns a random integer from a to b, inclusive. Each result is equally likely to occur. For example, RANDOM(1, 3) could return 1, 2, or 3.	AAP-3.E.2 Using random number generation in a program means each execution may produce a different result.

Simulations

TOPIC	3.16 Simulations
ENDURING UNDERSTANDING	AAP-3 Programmers break down problems into smaller and more manageable pieces. By creating procedures and leveraging parameters, programmers generalize processes that can be reused. Procedures allow programmers to draw upon existing code that has already been tested, allowing them to write programs more quickly and with more confidence.
LEARNING OBJECTIVE	AAP-3.F For simulations: Explain how computers can be used to represent real world outcomes or phenomena 1.A Compare simulations with real world context. 1.D
ESSENTIAL KNOWLEDGE	AAP-3.F.1 Simulations are abstractions of more complex objects or phenomena for a specific purpose.	AAP-3.F.2 A simulation is a representation that uses varying sets of values to reflect the changing state of a phenomenon.	AAP-3.F.3 Simulations often mimic real-world events with the purpose of drawing inferences, allowing investigation of a phenomenon without the constraints of the real world.	AAP-3.F.4 The process of developing an abstract simulation involves removing specific details or simplifying functionality.	AAP-3.F.5 Simulations can contain bias derived from the choices of real-world elements that were included or excluded.	AAP-3.F.6 Simulations are most useful when real-world events are impractical for experiments (e.g., too big, too small, too fast, too slow, too expensive, or too dangerous).	AAP-3.F.7 Simulations facilitate the formulation and refinement of hypotheses related to the objects or phenomena under consideration.	AAP-3.F.8 Random number generators can be used to simulate the variability that exists in the real world.

Algorithmic Efficiency

TOPIC	3.17 Algorithmic Efficiency
ENDURING UNDERSTANDING	AAP-4 There exist problems that computers cannot solve, and even when a computer can solve a problem, it may not be able to do so in a reasonable amount of time.
LEARNING OBJECTIVE	AAP-4.A For determining the efficiency of an algorithm: Explain the difference between algorithms that run in a reasonable amount of time and those that do not. 1.D Identify situations where a heuristic solution may be more appropriate. 1.D
ESSENTIAL KNOWLEDGE	AAP-4.A.1 A problem is a general description of a task that can (or cannot) be solved algorithmically. An instance of a problem also includes specific input. For example, sorting is a problem; sorting the list (2,3,1,7) is an instance of the problem.	AAP-4.A.2 A decision problem is a problem with a yes/no answer (e.g., is there a path from A to B?). An optimization problem is a problem with the goal of finding the best solution among many (e.g., what is the shortest path from A to B?).	AAP-4.A.3 Efficiency is an estimation of the amount of computational resources used by an algorithm. Efficiency is typically expressed as a function of the size of the input. (no Big-O needed)	AAP-4.A.4 An algorithm's efficiency is determined through formal or mathematical reasoning.	AAP-4.A.5 An algorithm's efficiency can be informally measured by determining the number of times a statement or group of statements executes.	AAP-4.A.6 Different correct algorithms for the same problem can have different efficiencies.	AAP-4.A.7 Algorithms with a polynomial efficiency or slower (constant, linear, square, cube, etc.) are said to run in a reasonable amount of time. Algorithms with exponential or factorial efficiencies are examples of algorithms that run in an unreasonable amount of time.	AAP-4.A.8 Some problems cannot be solved in a reasonable amount of time because there is no efficient algorithm for solving them. In these cases, approximate solutions are sought.	AAP-4.A.9 A heuristic is an approach to a problem that produces a solution that is not guaranteed to be optimal but may be used when techniques that are guaranteed to always find an optimal solution are impractical.

Undecidable Problems

TOPIC	3.18 Undecidable Problems
ENDURING UNDERSTANDING	AAP-4 There exist problems that computers cannot solve, and even when a computer can solve a problem, it may not be able to do so in a reasonable amount of time.
LEARNING OBJECTIVE	AAP-4.B Explain the existence of undecidable problems in computer science.‚ 1.A
ESSENTIAL KNOWLEDGE	AAP-4.B.1 A decidable problem is a decision problem for which an algorithm can be written to produce a correct output for all inputs (e.g., Is the number even?).	AAP-4.B.2 An undecidable problem is one for which no algorithm can be constructed that is always capable of providing a correct yes-or-no answer.	AAP-4.B.3 An undecidable problem may have some instances that have an algorithmic solution, but there is no algorithmic solution that could solve all instances of the problem.

Activities

Sample Activities	Predict and compare Provide students with a list of expressions with assignments. Ask them to predict the value of each variable after the assignment and then compare their answers to the output produced when these statements are put into a program.
	Using manipulatives When learning about conditionals, take a printout of a simple conditional statement and cut it into multiple sections. As students enter the classroom, hand them an envelope full of the paper strips, and ask them to reassemble the conditional in the proper order.
	Marking the text Provide students with program code that draws a square of side length 10 and a separate set of program code that uses side length 100. Ask students to mark up the sets of code to identify where they are different and to create a generalization by using parameters. Ask them to write a procedure that uses parameters to draw a square of any size.
	Think-pair-share Have students work in pairs to consider what factors would be the most important to prioritize in writing an algorithm to build the perfect master schedule for the school. Some considerations may include maximum class size, student preferences, and teacher availability. Have the pairs discuss and then report their results. Finally, discuss as a class how such programs may have to settle for a good enough solution when an exact solution may not be possible in a reasonable amount of time.

Arduino

Overview

CLASS PERIODS	~10
OVERVIEW	Arduino is an open-source hardware and software company, project and user community that designs and manufactures single-board microcontrollers and microcontroller kits for building digital devices. Its products are licensed under the GNU Lesser General Public License (LGPL) or the GNU General Public License (GPL),[1] permitting the manufacture of Arduino boards and software distribution by anyone. Arduino boards are available commercially in preassembled form or as do-it-yourself (DIY) kits. (wikipedia)
Essential Questions	Lesson Plans Coming Soon...

Unity

Overview

CLASS PERIODS	~20
OVERVIEW	Unity is so much more than the world's best real-time development platform it's also a robust ecosystem designed to enable your success. Join our dynamic community of creators so you can tap into what you need to achieve your vision.
Essential Questions	Lesson Plans Coming Soon...