CSAwesome2 AP CSA Java Course with College Board 2025-6 Revisions

Welcome to CSAwesome2! It’s time to start your journey to learn how to program with Java. A shortcut way to get to this site is to type in the url: course.csawesome.org

CSAwesome is a College Board endorsed curriculum for AP Computer Science A, an introductory college-level computer programming course in Java. If you are a teacher using this curriculum, please join the teaching CSAwesome group which will give you access to teacher resources at csawesome.org.

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ATTENTION high school women of color taking AP CSA or CSP: if you identify as female and as Black, Hispanic/Latina, and/or Native American, apply to participate in Sisters Rise Up. The goal of Sisters Rise Up is to help you succeed in your AP Computer Science course and on the exam. They offer one-hour help sessions several times a week and once a month special help sessions often with guest speakers from computing. If you enroll in Sisters Rise Up and send in your AP CS exam score by the end of August, you will be sent a gift card for $100. See the flyer and apply at https://tinyurl.com/55z7tyb9.

CSAwesome Units:

Table of Contents

• Assignments

• 1. Using Objects and Methods
  • 1.1. Introduction to Algorithms, Programming, and Compilers
    • 1.1.1. Algorithms
    • 1.1.2. First Java Program
    • 1.1.3. Compiling and Running Java Programs
    • 1.1.4. Java Keywords
    • 1.1.5. Syntax Errors and Debugging
    • 1.1.6. Reading Error Messages
    • 1.1.7. Run-time Errors
    • 1.1.8. Comments
    • 1.1.9. Debugging Challenge
    • 1.1.10. Summary
    • 1.1.11. AP Practice
  • 1.2. Variables and Data Types
    • 1.2.1. What is a Variable?
    • 1.2.2. Data Types
    • 1.2.3. Declaring Variables in Java
    • 1.2.4. Naming Variables
    • 1.2.5. Debugging Challenge : Weather Report
    • 1.2.6. Coding Challenge : Mad Libs
    • 1.2.7. Summary
    • 1.2.8. AP Practice
  • 1.3. Expressions and Output
    • 1.3.1. Output
    • 1.3.2. Expressions and Operators
    • 1.3.3. Compound Expressions
    • 1.3.4. The Remainder Operator
    • 1.3.5. Coding Challenge : Pay Calculator
    • 1.3.6. Summary
    • 1.3.7. AP Practice
  • 1.4. Assignment and Input
    • 1.4.1. Assignment Statements
    • 1.4.2. Data Types in Assignments
    • 1.4.3. Adding 1 to a Variable
    • 1.4.4. Input with Variables
    • 1.4.5. Coding Challenge : Dog Years
    • 1.4.6. Summary
    • 1.4.7. AP Practice
    • 1.4.8. AP Classroom Progress Check Unit 1 Part 1
  • 1.5. Casting and Ranges of Values
    • 1.5.1. Casting
    • 1.5.2. Rounding
    • 1.5.3. Range of Values
    • 1.5.4. Coding Challenge : Average 3 Numbers
    • 1.5.5. Bonus Challenge : Unicode
    • 1.5.6. Summary
    • 1.5.7. AP Practice
  • 1.6. Compound Assignment Operators
    • 1.6.1. Code Tracing Challenge and Operators Maze
    • 1.6.2. Summary
    • 1.6.3. Review/Practice for Unit 1 Part 1
  • 1.7. APIs and Libraries
    • 1.7.1. java.lang Package
    • 1.7.2. Turtle Library
    • 1.7.3. Coding Challenge : Turtle Drawing
    • 1.7.4. Summary
  • 1.8. Documentation with Comments and Preconditions
    • 1.8.1. Comments
    • 1.8.2. Preconditions and Postconditions
    • 1.8.3. Software Validity and Use-Case Diagrams
    • 1.8.4. Agile Software Development
    • 1.8.5. Coding Challenge: Preconditions in Algorithms
    • 1.8.6. Summary
    • 1.8.7. AP Practice
  • 1.9. Method Signatures
    • 1.9.1. Methods and Procedural Abstraction
    • 1.9.2. Method Calls
    • 1.9.3. Methods Signature, Parameters, Arguments
    • 1.9.4. Overloading
    • 1.9.5. Coding Challenge: Song with Parameters
    • 1.9.6. Summary
    • 1.9.7. AP Practice
    • 1.9.8. AP Classroom Progress Check Unit 1 Part 2
  • 1.10. Calling Class Methods
    • 1.10.1. Non-void Methods
    • 1.10.2. Common Errors with Methods
    • 1.10.3. Methods Outside the Class
    • 1.10.4. Coding Challenge: Ladder on Tower
    • 1.10.5. Summary
    • 1.10.6. AP Practice
  • 1.11. Using the Math Class
    • 1.11.1. Mathematical Functions
    • 1.11.2. Random Numbers
    • 1.11.3. Coding Challenge : Random Numbers
    • 1.11.4. Summary
  • 1.12. Objects - Instances of Classes
    • 1.12.1. What are Classes and Objects?
    • 1.12.2. Attributes and Behaviors
    • 1.12.3. Turtle Class
    • 1.12.4. Creating Turtle Objects
    • 1.12.5. Class Hierarchy and Inheritance
    • 1.12.6. Turtle Methods
    • 1.12.7. Coding Challenge : Draw Letters
    • 1.12.8. Summary
    • 1.12.9. AP Practice
  • 1.13. Creating and Initializing Objects: Constructors
    • 1.13.1. The World Class Constructors
    • 1.13.2. The Turtle Class Constructors
    • 1.13.3. Object Variables and References
    • 1.13.4. Constructor Signatures
    • 1.13.5. Arguments, Parameters, and Call by Value
    • 1.13.6. Coding Challenge: Custom Turtles
    • 1.13.7. Summary
    • 1.13.8. AP Practice
  • 1.14. Calling Instance Methods
    • 1.14.1. Class Methods vs. Instance Methods
    • 1.14.2. Method Signatures
    • 1.14.3. Method Calls
    • 1.14.4. Methods Calls with Arguments
    • 1.14.5. Methods that Return Values
    • 1.14.6. Coding Challenge : Turtle House
    • 1.14.7. Summary
    • 1.14.8. AP Practice
  • 1.15. Strings
    • 1.15.1. String references
    • 1.15.2. String Operators - Concatenation
    • 1.15.3. String Index and Length
    • 1.15.4. String Methods
    • 1.15.5. String Methods: length, substring, indexOf
    • 1.15.6. CompareTo and Equals
    • 1.15.7. Common Mistakes with Strings
    • 1.15.8. Coding Challenge : Pig Latin
    • 1.15.9. Summary
    • 1.15.10. AP Practice
    • 1.15.11. String Methods Game
    • 1.15.12. Review/Practice for Unit 1 Part 3 on Using Objects
  • 1.16. Unit Summary 1a (1.1-1.6)
    • 1.16.1. Concept Summary
    • 1.16.2. Java Keyword Summary
    • 1.16.3. Vocabulary Practice
    • 1.16.4. Common Mistakes
  • 1.17. Mixed Up Code Practice 1.1-1.6
  • 1.18. Toggle Mixed Up or Write Code Practice 1.1-1.6
  • 1.19. Coding Practice 1a (1.1-1.6)
  • 1.20. Multiple Choice Exercises for Unit 1a (1.1-1.6)
  • 1.21. Unit Summary 1b (1.7-1.15)
    • 1.21.1. Concept Summary
    • 1.21.2. Java Keyword Summary
    • 1.21.3. Vocabulary Practice
    • 1.21.4. Common Mistakes
  • 1.22. Mixed Up Code Practice 1b (1.7-1.15)
  • 1.23. Toggle Mixed Up or Write Code Practice 1b (1.7-1.15)
  • 1.24. Coding Practice 1b (1.7-1.15)
  • 1.25. Multiple Choice Exercises for Unit 1b (1.9-1.15)
    • 1.25.1. Easier Multiple Choice Questions
    • 1.25.2. Medium Multiple Choice Questions
    • 1.25.3. Hard Multiple Choice Questions
  • 1.26. Practice Test for Objects (1.12-1.14)
  • 1.27. Java Swing GUIs (optional)
  • 1.28. Unit 1 Free Response Question (FRQ) Practice
    • 1.28.1. FRQ Description of Level Class
    • 1.28.2. FRQ Practice
• 2. Selection and Iteration
  • 2.1. Algorithms with Selection and Repetition
    • 2.1.1. Selection
    • 2.1.2. Repetition
    • 2.1.3. Algorithms with Pseudocode and Flowcharts
    • 2.1.4. Coding Challenge : Algorithms
    • 2.1.5. Summary
  • 2.2. Boolean Expressions
    • 2.2.1. Testing Equality (==)
    • 2.2.2. Relational Operators (<, >)
    • 2.2.3. Testing with remainder (%)
    • 2.2.4. Coding Challenge : Prime Numbers POGIL
    • 2.2.5. Summary
    • 2.2.6. AP Practice
    • 2.2.7. Relational Operators Practice Game
  • 2.3. if Statements
    • 2.3.1. One-way selection
    • 2.3.2. Relational Operators in If Statements
    • 2.3.3. Two-way selection
    • 2.3.4. Common Errors with If Statements
    • 2.3.5. Coding Challenge: Magic 8 Ball
    • 2.3.6. Summary
    • 2.3.7. AP Practice
  • 2.4. Nested if Statements
    • 2.4.1. Multiway selection (else if)
    • 2.4.2. Dangling Else Statements
    • 2.4.3. Coding Challenge : Adventure
    • 2.4.4. Summary
    • 2.4.5. AP Practice
  • 2.5. Compound Boolean Expressions
    • 2.5.1. And (&&), Or (||), and Not (!)
    • 2.5.2. Truth Tables
    • 2.5.3. Short Circuit Evaluation
    • 2.5.4. Coding Challenge : Truth Tables POGIL
    • 2.5.5. Summary
    • 2.5.6. AP Practice
    • 2.5.7. Boolean Game
  • 2.6. Comparing Boolean Expressions (De Morgan’s Laws)
    • 2.6.1. De Morgan’s Laws
    • 2.6.2. Truth Tables
    • 2.6.3. Simplifying Boolean Expressions
    • 2.6.4. Comparing Objects
    • 2.6.5. String Equality
    • 2.6.6. Equality with New Strings
    • 2.6.7. Comparing with null
    • 2.6.8. Coding Challenge : Truth and Tracing Tables POGIL
    • 2.6.9. Summary
    • 2.6.10. AP Practice
    • 2.6.11. Review/Practice for Selection
  • 2.7. While Loops
    • 2.7.1. Three Steps to Writing a Loop
    • 2.7.2. Tracing Loops
    • 2.7.3. Common Errors with Loops
    • 2.7.4. Input-Controlled Loops
    • 2.7.5. Coding Challenge : Turtle Squares
    • 2.7.6. Summary
    • 2.7.7. AP Practice
  • 2.8. For Loops
    • 2.8.1. Three Parts of a For Loop
    • 2.8.2. Decrementing Loops
    • 2.8.3. Coding Challenge : Turtles Drawing Shapes
    • 2.8.4. Summary
    • 2.8.5. AP Practice
  • 2.9. Implementing Selection and Iteration Algorithms
    • 2.9.1. Accumulator Pattern for Sum/Average
    • 2.9.2. Input-Controlled Loop
    • 2.9.3. Loop with if and Minimum/Maximum
    • 2.9.4. Divisibility
    • 2.9.5. Finding Digits with / and %
    • 2.9.6. Math.random() in if Statements
    • 2.9.7. Frequency
    • 2.9.8. Coding Challenge : Prime Number Finder
    • 2.9.9. Summary
  • 2.10. Implementing String Algorithms
    • 2.10.1. While Find and Replace Loop
    • 2.10.2. For Loops: Reverse String
    • 2.10.3. Coding Challenge : String Replacement Cats and Dogs
    • 2.10.4. Summary
  • 2.11. Nested Iteration
    • 2.11.1. Nested Loops with Turtles
    • 2.11.2. Coding Challenge : Turtle Snowflakes
    • 2.11.3. Summary
  • 2.12. Informal Runtime Analysis of Loops
    • 2.12.1. Tracing Loops
    • 2.12.2. Counting Loop Iterations
    • 2.12.3. Analyzing Nested Loops
    • 2.12.4. Non-rectangular Nested Loops
    • 2.12.5. Coding Challenge : POGIL Analyzing Loops
    • 2.12.6. Summary
    • 2.12.7. Loop Analysis Game
    • 2.12.8. Review/Practice for Loops
  • 2.13. Unit Summary 2a Selection (2.1-2.6)
    • 2.13.1. Concept Summary
    • 2.13.2. Java Keyword Summary
    • 2.13.3. Vocabulary Practice
    • 2.13.4. Common Mistakes
  • 2.14. Selection Mixed Up Code Practice (2.1-2.6)
  • 2.15. Selection Toggle Mixed Up or Write Code Practice (2.1-2.6)
  • 2.16. Selection Coding Practice (2.1-2.6)
  • 2.17. Selection Multiple Choice Exercises (2.1-2.6)
    • 2.17.1. Easier Multiple Choice Questions
    • 2.17.2. Medium Multiple Choice Questions
    • 2.17.3. Hard Multiple Choice Questions
  • 2.18. Selection Free Response Question (FRQ) Game Practice (2.1-2.6)
    • 2.18.1. FRQ 1 Part A Description (2022)
    • 2.18.2. Warm up Exercises
    • 2.18.3. Solve the Problem
    • 2.18.4. AP Scoring Rubric
  • 2.19. FRQ Style Selection Coding Practice (2.1-2.6)
  • 2.20. Group Work - Remainder Operator (%)
    • 2.20.1. Going Beyond Remainder 4
    • 2.20.2. Look Deeper
    • 2.20.3. More Practice
    • 2.20.4. Long Division with a Remainder
    • 2.20.5. Dividing Evenly
    • 2.20.6. Describe the Remainder (%) Operator
  • 2.21. Unit Summary 2b Loops (2.7-2.12)
    • 2.21.1. Concept Summary
    • 2.21.2. Java Keyword Summary
    • 2.21.3. Vocabulary Practice
    • 2.21.4. Common Mistakes
  • 2.22. Loops Mixed Up Code Practice (2.7-2.12)
  • 2.23. Loops Toggle Mixed Up or Write Code Practice (2.7-2.12)
  • 2.24. Loops Coding Practice (2.7-2.12)
  • 2.25. Loops Multiple Choice Exercises (2.7-2.12)
    • 2.25.1. Easier Multiple Choice Questions
    • 2.25.2. Medium Multiple Choice Questions
    • 2.25.3. More Practice
  • 2.26. Unit 2 Test
  • 2.27. FRQ APCalendar for Loops and Control Structures
    • 2.27.1. 2019 APCalendar FRQ
    • 2.27.2. Part A: numberOfLeapYear()
    • 2.27.3. How to solve numberOfLeapYears()
    • 2.27.4. Part B: dayOfWeek()
  • 2.28. FRQ Self Divisor A
    • 2.28.1. How to solve this problem
    • 2.28.2. Video - One way to code the solution
  • 2.29. FRQ String Scramble A
    • 2.29.1. How to solve this problem
    • 2.29.2. Figuring out the algorithm
    • 2.29.3. Write the Code
    • 2.29.4. Video - One way to code the solution
  • 2.30. Magpie Chatbot Lab
    • 2.30.1. Magpie ChatBot Lab
    • 2.30.2. Activity 2: Running Simplified Magpie Code
    • 2.30.3. Activity 3: Better Keyword Detection
    • 2.30.4. Activity 4: Responses that Transform Statements
    • 2.30.5. Mixed Up Code Practice
  • 2.31. Consumer Review Lab
    • 2.31.1. Activity 0 Analyzing Reviews
    • 2.31.2. Activity 1 : Sentiment Value
    • 2.31.3. Activity 2 :Total Sentiment Value and Star Ratings
    • 2.31.4. Activity 3 : Autogenerate a Fake Review
    • 2.31.5. Activity 4 : Create a More Positive or Negative Review
    • 2.31.6. Activity 5 : Open-ended Activity
• 3. Class Creation
  • 3.1. Abstraction and Program Design
    • 3.1.1. Object-Oriented Design
    • 3.1.2. UML Class Diagrams
    • 3.1.3. Abstraction
    • 3.1.4. Data Abstraction
    • 3.1.5. Procedural Abstraction
    • 3.1.6. Group Challenge : Game Design
    • 3.1.7. Summary
  • 3.2. Impact of Program Design
    • 3.2.1. Groupwork: Impacts of CS
    • 3.2.2. Summary
  • 3.3. Anatomy of a Java Class
    • 3.3.1. Parts of a Class
    • 3.3.2. Designing a Class
    • 3.3.3. Data encapsulation
    • 3.3.4. Instance Variables
    • 3.3.5. Instance Methods
    • 3.3.6. Coding Challenge : Virtual Pet Class
    • 3.3.7. Design a Class for your Community
    • 3.3.8. Summary
    • 3.3.9. AP Practice
  • 3.4. Writing Constructors
    • 3.4.1. Constructor Signature
    • 3.4.2. The Job of a Constructor
    • 3.4.3. Coding Challenge : Student Class
    • 3.4.4. Design a Class for your Community
    • 3.4.5. Summary
    • 3.4.6. AP Practice
  • 3.5. Methods: How to Write Them
    • 3.5.1. Defining and Calling Methods
    • 3.5.2. void Methods
    • 3.5.3. Non-void Methods
    • 3.5.4. Accessors / Getters
    • 3.5.5. toString
    • 3.5.6. Mutators / Setters
    • 3.5.7. Parameters
    • 3.5.8. Methods with Parameters that Return Calculated values
    • 3.5.9. Coding Challenge : Class Pet
    • 3.5.10. Design a Class for your Community
    • 3.5.11. Summary
    • 3.5.12. AP Practice
  • 3.6. Methods: Passing and Returning References of an Object
    • 3.6.1. Objects as Instance Variables
    • 3.6.2. Objects as Arguments
    • 3.6.3. Copying Parameter Objects
    • 3.6.4. Parameter of the Same Class Type
    • 3.6.5. Returning Objects
    • 3.6.6. Coding Challenge : Friends and Birthdays
    • 3.6.7. Summary
  • 3.7. Class (static) Variables and Methods
    • 3.7.1. Class Methods
    • 3.7.2. Class Variables
    • 3.7.3. final keyword
    • 3.7.4. Coding Challenge : Static Song and counter
    • 3.7.5. Summary
  • 3.8. Scope and Access
    • 3.8.1. Class, Method, and Block Level Scope
    • 3.8.2. Local Variables
    • 3.8.3. Coding Challenge : Debugging
    • 3.8.4. Summary
    • 3.8.5. AP Practice
  • 3.9. this Keyword
    • 3.9.1. this.instanceVariable
    • 3.9.2. this as an Argument
    • 3.9.3. Coding Challenge : Bank Account
    • 3.9.4. Summary
    • 3.9.5. AP Practice
  • 3.10. Unit 3 Summary
    • 3.10.1. Concept Summary
    • 3.10.2. Java Keyword Summary
    • 3.10.3. Vocabulary Practice
    • 3.10.4. Common Mistakes
  • 3.11. Mixed Up Code Practice
  • 3.12. Toggle Mixed Up or Write Code Practice
  • 3.13. Multiple-Choice Exercises - Objects and Classes
  • 3.14. Unit 3 Test
  • 3.15. Free Response Question (FRQ) - StepTracker Class
    • 3.15.1. StepTracker Class FRQ
    • 3.15.2. Determining the Instance Variables
    • 3.15.3. Writing the Class Header and Constructor
    • 3.15.4. Writing the Accessor Method activeDays
    • 3.15.5. Writing the Mutator Method addDailySteps
    • 3.15.6. Writing the Accessor Method averageSteps
  • 3.16. Free Response Question - Time
  • 3.17. Free Response Question - APLine
    • 3.17.1. Try and Solve It
  • 3.18. College Board Celebrity and Data Labs
  • 3.19. Design a Class for your Community Project
    • 3.19.1. Code your Class
    • 3.19.2. Optional Swing GUI
• 4. Data Collections
  • 4.1. Ethical and Social Issues Around Data Collection
    • 4.1.1. Data Privacy
    • 4.1.2. Data and Bias
    • 4.1.3. Summary
  • 4.2. Data Sets
    • 4.2.1. Summary
  • 4.3. Array Creation and Access
    • 4.3.1. Declaring and Creating an Array
    • 4.3.2. Using new to Create Arrays
    • 4.3.3. Initializer Lists to Create Arrays
    • 4.3.4. Array length
    • 4.3.5. Access and Modify Array Values
    • 4.3.6. Coding Challenge : Countries Array
    • 4.3.7. Design an Array of Objects for your Community
    • 4.3.8. Summary
    • 4.3.9. AP Practice
    • 4.3.10. Arrays Game
  • 4.4. Array Traversals
    • 4.4.1. Index Variables
    • 4.4.2. Loops to Traverse Arrays
    • 4.4.3. Arrays as Objects and Parameters
    • 4.4.4. Looping through Part of an Array
    • 4.4.5. Common Errors When Looping Through an Array
    • 4.4.6. Enhanced For-Loop (For-Each) for Arrays
    • 4.4.7. Enhanced For Loop Limitations
    • 4.4.8. Traversing Arrays of Objects
    • 4.4.9. Coding Challenge : SpellChecker
    • 4.4.10. Design an Array of Objects for your Community
    • 4.4.11. Summary
    • 4.4.12. Arrays Game
  • 4.5. Implementing Array Algorithms
    • 4.5.1. Accumulator Pattern for Sum/Average
    • 4.5.2. Min, Max, Search Algorithms
    • 4.5.3. Looping From Back to Front
    • 4.5.4. Test Property
    • 4.5.5. Pairs and Duplicates in Array
    • 4.5.6. Rotating Array Elements
    • 4.5.7. Reversing an Array
    • 4.5.8. Review and FRQ Practice for Arrays
  • 4.6. Using Text Files
    • 4.6.1. Java File, Scanner, and IOException Classes
    • 4.6.2. Reading in Data with Scanner
    • 4.6.3. Loop to Read in a File
    • 4.6.4. Save File Data into an Array
    • 4.6.5. Split Strings
    • 4.6.6. Object-Oriented Design with CSV Files
    • 4.6.7. Coding Challenge: Array of Pokemon from Input File
    • 4.6.8. Optional Challenge with a Dataset
    • 4.6.9. Summary
  • 4.7. Wrapper Classes - Integer and Double
    • 4.7.1. Creating Integer and Double Objects
    • 4.7.2. Autoboxing and Unboxing
    • 4.7.3. Parsing Strings to Numbers
    • 4.7.4. Coding Challenge: Pokemon Speed
    • 4.7.5. Summary
  • 4.8. ArrayList and its Methods
    • 4.8.1. import java.util.ArrayList
    • 4.8.2. Declaring and Creating ArrayLists
    • 4.8.3. ArrayList Methods
    • 4.8.4. size()
    • 4.8.5. add(obj)
    • 4.8.6. add(index,obj)
    • 4.8.7. remove(index)
    • 4.8.8. get(index) and set(index, obj)
    • 4.8.9. Comparing arrays and ArrayLists
    • 4.8.10. Coding Challenge : FRQ Digits
    • 4.8.11. Summary
  • 4.9. ArrayList Traversals
    • 4.9.1. Enhanced For Loop
    • 4.9.2. For Loops and IndexOutOfBounds Exception
    • 4.9.3. While Loop
    • 4.9.4. Reading in Files with java.nio.file
    • 4.9.5. ArrayList of Student Objects
    • 4.9.6. Coding Challenge : FRQ Word Pairs
    • 4.9.7. Summary
  • 4.10. Implementing ArrayList Algorithms
    • 4.10.1. Add/Remove Elements
    • 4.10.2. Min, Max, Sum, Average
    • 4.10.3. Finding a property
    • 4.10.4. Pairs and Duplicates
    • 4.10.5. Shift/Rotate an ArrayList
    • 4.10.6. Reversing an ArrayList
    • 4.10.7. Multiple or Parallel Data Structures
    • 4.10.8. Summary
    • 4.10.9. Review and FRQ Practice with ArrayLists
  • 4.11. 2D Array Creation and Access
    • 4.11.1. Array Storage
    • 4.11.2. Declaring 2D Arrays
    • 4.11.3. Initializer Lists for 2D Arrays
    • 4.11.4. Set Values in a 2D Array
    • 4.11.5. Get a Value from a 2D Array
    • 4.11.6. 2D Array Row and Column length
    • 4.11.7. Coding Challenge : ASCII Art
    • 4.11.8. Summary
    • 4.11.9. 2D Arrays Game
  • 4.12. 2D Array Traversals: Nested Loops
    • 4.12.1. Nested Loops
    • 4.12.2. Row-Major and Column-Major Traversals
    • 4.12.3. Enhanced For-Each Loop for 2D Arrays
    • 4.12.4. 2D Array of Objects
    • 4.12.5. Coding Challenge : Picture Lab
    • 4.12.6. Summary
    • 4.12.7. AP Practice
    • 4.12.8. 2D Arrays and Loops Game
  • 4.13. Implementing 2D Array Algorithms
    • 4.13.1. Sum, Average, Min, Max 2D Array Algorithms
    • 4.13.2. Subsection of a 2D Array for a Property
    • 4.13.3. Duplicates in 2D Arrays
    • 4.13.4. Rotate and Reverse
    • 4.13.5. Review and FRQ Practice with 2D arrays
  • 4.14. Searching Algorithms
    • 4.14.1. Linear Search
    • 4.14.2. Linear Search with 2D Arrays
    • 4.14.3. Binary Search
    • 4.14.4. Runtimes
    • 4.14.5. Coding Challenge : Search Runtimes
    • 4.14.6. Summary
  • 4.15. Sorting Algorithms
    • 4.15.1. Selection Sort
    • 4.15.2. Insertion Sort
    • 4.15.3. Coding Challenge : Sort Runtimes
    • 4.15.4. Summary
    • 4.15.5. Search/Sort Multiple-Choice Exercises
  • 4.16. Recursion
    • 4.16.1. Recursive Call
    • 4.16.2. Why use Recursion?
    • 4.16.3. Factorial Method
    • 4.16.4. Base Case
    • 4.16.5. Tracing Recursive Methods
    • 4.16.6. Tracing Challenge : Recursion
    • 4.16.7. Summary
  • 4.17. Recursive Searching and Sorting
    • 4.17.1. Recursive Binary Search
    • 4.17.2. Merge Sort
    • 4.17.3. Tracing Challenge : Recursive Search and Sort
    • 4.17.4. Summary
    • 4.17.5. Summary and Review Exercises
  • 4.18. Arrays Summary
    • 4.18.1. Concept Summary
    • 4.18.2. Java Keyword Summary
    • 4.18.3. Vocabulary Practice
    • 4.18.4. Common Mistakes
  • 4.19. Arrays Mixed Up Code Practice
  • 4.20. Arrays Toggle Mixed Up or Write Code Practice
  • 4.21. Arrays Code Practice
    • 4.21.1. More Practice
  • 4.22. More Code Practice with Arrays
  • 4.23. Arrays Multiple-Choice Exercises
    • 4.23.1. Easier Multiple Choice Questions
    • 4.23.2. Medium Multiple Choice Questions
    • 4.23.3. Hard Multiple Choice Questions
  • 4.24. Practice Exam for Arrays
  • 4.25. Free Response - Horse Barn A
    • 4.25.1. How to solve this problem
    • 4.25.2. Try It!
    • 4.25.3. Video - One way to code the solution
  • 4.26. Free Response - Horse Barn B
    • 4.26.1. How to solve this problem
    • 4.26.2. Video - One way to code the solution
  • 4.27. Free Response - Self Divisor B
    • 4.27.1. How to solve this problem
    • 4.27.2. Video - One way to code the solution
  • 4.28. Free Response - Sound A
    • 4.28.1. How to Solve This
    • 4.28.2. Mixed Up Code
    • 4.28.3. Try and Solve Part A
  • 4.29. Free Response - Sound B
    • 4.29.1. How to Solve This
    • 4.29.2. Mixed Up Code
    • 4.29.3. Try and Solve Part B
  • 4.30. Free Response - Number Cube A
    • 4.30.1. How to Solve
    • 4.30.2. Mixed Up Code
    • 4.30.3. Try and Solve Part A
  • 4.31. Free Response - Number Cube B
    • 4.31.1. How to Solve
    • 4.31.2. Mixed Up Code
    • 4.31.3. Try and Solve Part B
  • 4.32. ArrayList Summary
    • 4.32.1. Concept Summary
    • 4.32.2. Vocabulary Practice
    • 4.32.3. Common Mistakes
  • 4.33. ArrayList Mixed Up Code Practice
  • 4.34. ArrayList Toggle Mixed Up or Write Code Practice
  • 4.35. Code Practice with ArrayLists
  • 4.36. ArrayList Multiple-Choice Exercises
    • 4.36.1. ArrayList Easier Multiple Choice Questions
    • 4.36.2. ArrayList Medium Multiple Choice Questions
    • 4.36.3. ArrayList Hard Multiple Choice Questions
  • 4.37. Free Response - String Scramble B
    • 4.37.1. How to solve this problem
    • 4.37.2. The Algorithm
    • 4.37.3. Try and Solve It
  • 4.38. Free Response - Climbing Club A
    • 4.38.1. How To Solve This
    • 4.38.2. Try and Solve It
    • 4.38.3. Video - One way to code the solution
  • 4.39. Free Response - Climbing Club B
    • 4.39.1. Walk Through the Example
    • 4.39.2. How To Solve This
    • 4.39.3. Try and Solve It
    • 4.39.4. Video - One way to code the solution
  • 4.40. Free Response - Climbing Club C
    • 4.40.1. Try it Out
  • 4.41. Free Response - CookieOrder A
    • 4.41.1. How to Solve This
    • 4.41.2. Mixed Up Code
    • 4.41.3. Solve Part A
  • 4.42. Free Response - CookieOrder B
    • 4.42.1. How to Solve This
    • 4.42.2. Mixed Up Code
    • 4.42.3. Solve Part B
  • 4.43. Free Response - StringFormatter A
    • 4.43.1. Part A
    • 4.43.2. How to Solve Part A
    • 4.43.3. Put the Code in Order
    • 4.43.4. Write the Code
  • 4.44. Free Response - StringFormatter B
    • 4.44.1. Part B
    • 4.44.2. How to Solve Part B
    • 4.44.3. Put the Code in Order
    • 4.44.4. Write the Code
  • 4.45. Free Response - Delimiters A
    • 4.45.1. Part A
    • 4.45.2. Check your understanding of the question
    • 4.45.3. How to Solve Part A
    • 4.45.4. Write the Code
  • 4.46. Free Response - Delimiters B
    • 4.46.1. Part B
    • 4.46.2. Check your understanding of the Question
    • 4.46.3. How to Solve Part B
    • 4.46.4. Write the Code
  • 4.47. Free Response - Grid World A
    • 4.47.1. Necessary Preliminary Information
    • 4.47.2. Check your understanding of the question
    • 4.47.3. How to Solve Part A
    • 4.47.4. Write the Code
  • 4.48. Search/Sort Multiple-Choice Exercises
    • 4.48.1. Easier Search/Sort Multiple Choice Questions
    • 4.48.2. Medium Search/Sort Multiple Choice Questions
    • 4.48.3. Hard Search/Sort Multiple Choice Questions
  • 4.49. 2D Arrays Summary
    • 4.49.1. Concept Summary
    • 4.49.2. Vocabulary Practice
    • 4.49.3. Common Mistakes
  • 4.50. 2D Arrays Mixed Up Code Practice
  • 4.51. 2D Arrays Toggle Mixed Up or Write Code Practice
  • 4.52. Code Practice with 2D Arrays
  • 4.53. More Code Practice with 2D Arrays
  • 4.54. 2D Arrays Multiple-Choice Exercises
    • 4.54.1. 2D Arrays Easier Multiple Choice Questions
    • 4.54.2. 2D Arrays Medium Multiple Choice Questions
    • 4.54.3. 2D Arrays Hard Multiple Choice Questions
  • 4.55. Free Response - Gray Image A
    • 4.55.1. How to solve this problem
    • 4.55.2. Algorithm
    • 4.55.3. Try and Solve It
    • 4.55.4. Video - One way to code the solution
  • 4.56. Free Response - Gray Image B
    • 4.56.1. How to solve this problem
    • 4.56.2. Algorithm
    • 4.56.3. Try and Solve It
    • 4.56.4. Video - One way to code the solution
  • 4.57. Free Response - Route Cipher A
    • 4.57.1. How to Solve This
    • 4.57.2. The Algorithm
    • 4.57.3. Try And Solve It
  • 4.58. Free Response - Route Cipher B
    • 4.58.1. How to Solve This
    • 4.58.2. Solve Part B
    • 4.58.3. Alternate Recursive Solution
  • 4.59. Recursion Summary
    • 4.59.1. Concept Summary
    • 4.59.2. Vocabulary Practice
    • 4.59.3. Common Mistakes
  • 4.60. Recursion Mixed Up Code Practice
  • 4.61. Recursion More Mixed Up Code Practice
  • 4.62. Recursion Toggle Mixed Up or Write Code Practice
  • 4.63. Code Practice for Recursion
  • 4.64. Recursion Exercises
    • 4.64.1. Recursion Base Case Practice
    • 4.64.2. Recursion Easier Multiple Choice Questions
    • 4.64.3. Recursion Medium Multiple Choice Questions
    • 4.64.4. Recursion Hard Multiple Choice Questions
  • 4.65. College Board Celebrity and Data Labs
  • 4.66. College Board Picture Lab and Steganography Lab for 2D Arrays
    • 4.66.1. Picture Lab A1 - A3
    • 4.66.2. Picture Lab A4: 2D Arrays in Java
    • 4.66.3. Picture Lab A5: Modifying a Picture
    • 4.66.4. Picture Lab A6: Mirroring Pictures
    • 4.66.5. Picture Lab A7: Mirroring Part of a Picture
    • 4.66.6. Picture Lab A8: Creating a Collage
    • 4.66.7. Picture Lab A9: Simple Edge Detection
• 5. Inheritance (optional)
  • 5.1. Inheritance, Superclass, Subclass
    • 5.1.1. Subclass extends Superclass
    • 5.1.2. Why Use Inheritance?
    • 5.1.3. is-a vs. has-a Relationships
    • 5.1.4. is-a Substitution Test
    • 5.1.5. Coding Challenge : Online Store
    • 5.1.6. Summary
  • 5.2. Inheritance and Constructors
    • 5.2.1. Chain of initialization
    • 5.2.2. Coding Challenge : Square is-a Rectangle
    • 5.2.3. Summary
  • 5.3. Overriding Methods
    • 5.3.1. Overloading Methods
    • 5.3.2. Inherited Get/Set Methods
    • 5.3.3. Coding Challenge : Pet Sounds
    • 5.3.4. Summary
  • 5.4. super Keyword
    • 5.4.1. Coding Challenge : Customer Info
    • 5.4.2. Summary
  • 5.5. Inheritance Hierarchies
    • 5.5.1. Superclass References
    • 5.5.2. Superclass Method Parameters
    • 5.5.3. Superclass Arrays and ArrayLists
    • 5.5.4. Coding Challenge : Shopping Cart
    • 5.5.5. Summary
  • 5.6. Polymorphism
    • 5.6.1. Coding Challenge : Shopping Cart 2
    • 5.6.2. Summary
  • 5.7. Object Superclass
    • 5.7.1. toString() method
    • 5.7.2. equals Method
    • 5.7.3. Overriding the equals Method
    • 5.7.4. Coding Challenge : Savings Account
    • 5.7.5. Summary
  • 5.8. Inheritance Summary
    • 5.8.1. Concept Summary
    • 5.8.2. Java Keyword Summary
    • 5.8.3. Vocabulary Practice
    • 5.8.4. Common Mistakes
  • 5.9. Free Response Questions
    • 5.9.1. Free Response - Trio A
    • 5.9.2. Trio Student Solution 1
    • 5.9.3. Trio Student Solution 2
    • 5.9.4. Trio Student Solution 3
  • 5.10. Mixed Up Code Practice
  • 5.11. Toggle Mixed Up or Write Code Practice
  • 5.12. Code Practice with Object Oriented Concepts
  • 5.13. Inheritance Multiple-Choice Exercises
    • 5.13.1. Easier Multiple Choice Questions
    • 5.13.2. Medium Multiple Choice Questions
    • 5.13.3. Hard Multiple Choice Questions
    • 5.13.4. More Practice
  • 5.14. College Board Celebrity Lab
• 6. Post Test and Survey
  • 6.1. Post Test
  • 6.2. Post-Survey
• 7. Preparing for the Exam
  • 7.1. Preparing for the AP CSA Exam
  • 7.2. Exam 1 for the AP CSA Exam (not timed)
  • 7.3. Exam 2 for the AP CSA Exam (not timed)
  • 7.4. Exam 3 for the AP CSA Exam (not timed)
  • 7.5. Exam 4 for the AP CSA Exam (not timed)
  • 7.6. Exam 5 for the AP CSA Exam (not timed)
• 8. Timed Multiple-Choice Exams
  • 8.1. Practice Exam 1 for the AP CSA Exam
  • 8.2. Practice Exam 2 for the AP CSA Exam
  • 8.3. Practice Exam 3 for the AP CSA Exam
  • 8.4. Practice Exam X
  • 8.5. AP Bowl 2021 - Part A
• 9. Mixed Up Code - Free Response Practice
  • 9.1. RandomStringChooser - Part A Parsons
    • 9.1.1. Mixed Up Code Practice
    • 9.1.2. More Mixed Up Code Practice
  • 9.2. RandomStringChooser - Part A
    • 9.2.1. Try and Solve It - Again
  • 9.3. RandomStringChooser - Part B Parsons
  • 9.4. RandomStringChooser - Part B - 2nd time
    • 9.4.1. Try and Solve It - Again
• 10. Free Response Practice
  • 10.1. RandomStringChooser - Part A
    • 10.1.1. Try and Solve It
  • 10.2. RandomStringChooser - Part B
    • 10.2.1. Try and Solve It
  • 10.3. StringCoder - Part A
    • 10.3.1. Try and Solve It
  • 10.4. StringCoder - Part B
    • 10.4.1. Try and Solve It
  • 10.5. StudentAnswerSheet - Part A
    • 10.5.1. Try and Solve It
  • 10.6. StudentAnswerSheet - Part B
    • 10.6.1. Try and Solve It
  • 10.7. SkyView - Part A
    • 10.7.1. Try and Solve It
  • 10.8. SkyView - Part B
    • 10.8.1. Try and Solve It
  • 10.9. Hidden Word - Write Class
    • 10.9.1. Try and Solve It
  • 10.10. ArrayTester - Part A
    • 10.10.1. Try and Solve It
  • 10.11. ArrayTester - Part B
    • 10.11.1. Try and Solve It
  • 10.12. NumberGroup - Part B
    • 10.12.1. Try and Solve It
  • 10.13. NumberGroup - Part C
    • 10.13.1. Try and Solve It
• 11. Stories
  • 11.1. Challenges In Computing
    • 11.1.1. Impostor Syndrome
    • 11.1.2. A Lack of Diversity
  • 11.2. Meet The Interviewees
    • 11.2.1. Anaya Taylor
    • 11.2.2. Bryan Hickerson
    • 11.2.3. Briceida Mariscal
    • 11.2.4. Carla De Lira
    • 11.2.5. Camille Mbayo
    • 11.2.6. Destini Deinde-Smith
    • 11.2.7. Eric Espinoza
    • 11.2.8. Dr. Gloria Opoku-Boateng
    • 11.2.9. Dr. Juan Gilbert
    • 11.2.10. Luisa Morales
    • 11.2.11. Lucas Vocos
    • 11.2.12. Lien Diaz
    • 11.2.13. Milly Rodriguez
    • 11.2.14. Dr. Nettrice Gaskins
• 12. Hidden Items

Index

• Index

• Search Page

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(last revised 1/2025)

© Copyright 2014-2025 Barb Ericson, Univ. Michigan; 2019-2025 Beryl Hoffman, Elms College; 2023-2025 Peter Seibel, Berkeley High School. All rights reserved.

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