Mr. Adiletta

AP Computer Science A

Java, from the first line you type to the algorithms that sort a collection of ten thousand things. Four units, following College Board's framework exactly. A Do Now every day, tagged to the same objectives the exam is written against.

Start Unit 1Assignments

The course

Start here, then four units

College Board rebuilt this course for Fall 2025: ten units became four. Below is that framework — 56 topics, each unit carrying its own weight on the exam, with a prologue in front that isn't on the exam at all.

00lockedHow the Machine ThinksBefore you write a line of Java, you should know what a computer actually is: switches, numbers built out of switches, and a set of tools that will not think for you — ending with a real Java project you created and ran.Inside · 19 min read
  1. What makes something a program
  2. Gates: how switches make a decision
  3. How can wires and electricity think?
  4. Build the tables yourself
  5. Counting in binary
  6. Hexadecimal, and why anyone bothers
  7. Your tools
  8. How you turn work in
  9. Before the next unit
8 quick checksabstraction ladderstepperlogic gate scroller
01lockedUsing Objects and Methods15–25% of the examBy the end of this unit you can read a line of Java out loud, say what every piece of it does, and predict what it prints before you run it.Inside · 18 min read
  1. 1.1 · Algorithms, programming, and compilers
  2. 1.2 · Variables and data types
  3. 1.3 · Expressions and output
  4. 1.4 · Assignment statements and input
  5. 1.5 · Casting and the range of a variable
  6. 1.6 · Compound assignment operators
  7. 1.7 · APIs and libraries
  8. 1.8 · Comments
  9. 1.9 · Method signatures
  10. 1.10 · Calling class methods
  11. 1.11 · The Math class
  12. 1.12 · Objects: instances of classes
  13. 1.13 · Creating objects
  14. 1.14 · Calling instance methods
  15. 1.15 · String manipulation
  16. Where this goes next
27 quick checksscrollytellingobject reference diagramsobject instantiation yard02lockedSelection and Iteration25–35% of the examBuild Magpie — a chatbot that reads what a person typed and answers it — and in doing so learn the two things that turn a list of instructions into a program that responds to the world: decisions, and repetition.Inside · 32 min read
  1. The project · Magpie
  2. 2.1 · Algorithms with selection and repetition
  3. 2.2 · Boolean expressions
  4. 2.3 · if statements
  5. 2.4 · Nested if statements
  6. 2.5 · Compound Boolean expressions
  7. 2.6 · Comparing Boolean expressions
  8. 2.7 · while loops
  9. 2.8 · for loops
  10. 2.9 · Implementing selection and iteration algorithms
  11. 2.10 · Implementing String algorithms
  12. 2.11 · Nested iteration
  13. 2.12 · Informal run-time analysis
  14. Finishing Magpie
  15. Where this goes next
29 quick checksstepperloop tracerchatbot sandboxtruth tablescode exercises+1 more03lockedClass Creation10–18% of the examBuild MonsterBattle — a turn-based fight you can play — starting with the Monster class underneath it, written by you from nothing, deciding what an object knows, what it can do, and what it refuses to let anyone touch.Inside · 27 min read
  1. The projects · Monster, then MonsterBattle
  2. 3.1 · Abstraction and program design
  3. 3.2 · Impact of program design
  4. 3.3 · Anatomy of a class
  5. 3.4 · Constructors
  6. 3.5 · Methods, and how to write them
  7. 3.6 · Passing and returning references
  8. 3.7 · Class variables and methods
  9. 3.8 · Scope and access
  10. 3.9 · The this keyword
  11. Finishing the projects
  12. Where this goes next
26 quick checksstepperobject reference diagramsobject instantiation yardcode exercisesdebugging drills04lockedData Collections30–40% of the examBuild four things that each hold thousands of values at once — a dataset you parse, a photograph you edit pixel by pixel, a playable 2048 and a sorting bench — and learn the arrays, ArrayLists, 2D arrays and algorithms underneath all four.Inside · 42 min read
  1. What you will build
  2. 4.1 · Ethical and social issues around data collection
  3. 4.2 · Introduction to using data sets
  4. 4.3 · Array creation and access
  5. 4.4 · Array traversals
  6. 4.5 · Implementing array algorithms
  7. 4.6 · Using text files
  8. 4.7 · Wrapper classes
  9. 4.8 · ArrayList methods
  10. 4.9 · ArrayList traversals
  11. 4.10 · Implementing ArrayList algorithms
  12. 4.11 · 2D array creation and access
  13. 4.12 · 2D array traversals
  14. 4.13 · Implementing 2D array algorithms
  15. 4.14 · Searching algorithms
  16. 4.15 · Sorting algorithms
  17. 4.16 · Recursion
  18. 4.17 · Recursive searching and sorting
  19. The projects, in full
43 quick checksvideoArrayList sandboxloop tracercall stack viewerarray explorer+2 more

Every day

The Do Now

One multiple-choice question, sometimes two, waiting when you sit down. Same tags College Board uses, so a miss tells you exactly which objective to go back to. 76 posted so far.

All assignments

How you're measured

5 thinking practices

The exam tests what you can do, not what you can recite: design code, develop code, analyze code, document code and computing systems, use computers responsibly. Every question here is tagged with the practice it exercises. There are 12 skills, from 1.A to 5.A.

Outside this site

Practice, not more reading

  • CodingBat — short, focused method problems with instant right/wrong feedback.
  • SoloLearn — a phone-friendly Java course for reviewing between assignments.
  • Codecademy — a slower, guided walk through Java for a topic that didn't stick.