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 — 53 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.Inside · 15 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
9 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 · 17 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 instantiation yard02lockedSelection and Iteration25–35% of the examDecisions and repetition, the two things that turn a list of instructions into a program that responds to the world.Inside · 19 min read
  1. 2.1 · Algorithms with selection and repetition
  2. 2.2 · Boolean expressions
  3. 2.3 · if statements
  4. 2.4 · Nested if statements
  5. 2.5 · Compound Boolean expressions
  6. 2.6 · Comparing Boolean expressions
  7. 2.7 · while loops
  8. 2.8 · for loops
  9. 2.9 · Implementing selection and iteration algorithms
  10. 2.10 · Implementing String algorithms
  11. 2.11 · Nested iteration
  12. 2.12 · Informal run-time analysis
  13. The project · Magpie
  14. Where this goes next
29 quick checksloop tracerchatbot sandboxtruth tablescode exercisesdebugging drills03lockedClass Creation10–18% of the examStop using other people's classes and write your own, deciding what an object knows, what it can do, and what it refuses to let anyone touch.Inside · 17 min read
  1. 3.1 · Abstraction and program design
  2. 3.2 · Impact of program design
  3. 3.3 · Anatomy of a class
  4. 3.4 · Constructors
  5. 3.5 · Methods, and how to write them
  6. 3.6 · Passing and returning references
  7. 3.7 · Class variables and methods
  8. 3.8 · Scope and access
  9. 3.9 · The this keyword
  10. The projects · Monster, then MonsterBattle
  11. Where this goes next
23 quick checksobject reference diagramsobject instantiation yarddebugging drills04lockedData Collections30–40% of the examArrays, ArrayLists, 2D arrays, and the searching, sorting and recursion that make thousands of values as manageable as one.Inside · 39 min read
  1. 4.1 · Ethical and social issues around data collection
  2. 4.2 · Introduction to using data sets
  3. 4.3 · Array creation and access
  4. 4.4 · Array traversals
  5. 4.5 · Implementing array algorithms
  6. 4.6 · Using text files
  7. 4.7 · Wrapper classes
  8. 4.8 · ArrayList methods
  9. 4.9 · ArrayList traversals
  10. 4.10 · Implementing ArrayList algorithms
  11. 4.11 · 2D array creation and access
  12. 4.12 · 2D array traversals
  13. 4.13 · Implementing 2D array algorithms
  14. 4.14 · Searching algorithms
  15. 4.15 · Sorting algorithms
  16. 4.16 · Recursion
  17. 4.17 · Recursive searching and sorting
  18. The projects
40 quick checksvideoloop tracercall stack viewerarray explorercode exercises+1 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. 67 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.