The Ultimate Guide to AP Computer Science A + Study Guide

What to Know, How to Prepare & Free Study Resources

AP Computer Science A is one of the fastest-growing AP exams — and for good reason. Whether you're aiming for a career in tech, engineering, data science, or just want to build problem-solving skills that translate to any field, this course gives you a college-level foundation in programming and computational thinking.

And starting in 2025–26, the course has been completely restructured. The old 10-unit framework has been condensed into 4 focused units, Inheritance has been removed from the exam, and File I/O (reading data with Scanner and File) has been added. If you're using study materials from last year, they may not match the current exam.

Here's everything you need to know to prepare for the AP CSA exam.

What Does AP Computer Science A Cover?

The course teaches Java programming through four units, each building on the last:

Unit	Topics	Exam Weight
1: Programming Fundamentals	Variables, types, operators, conditionals, loops, strings, Math class	15–25%
2: Data Structures	1D arrays, ArrayLists, 2D arrays, traversals, searching, File I/O	25–35%
3: Algorithms & Control	Sorting, algorithm analysis, nested loops, recursive thinking	15–25%
4: Software Design	Classes, objects, methods, encapsulation, interfaces, program design	30–40%

Unit 4 is the heavyweight — it accounts for up to 40% of the exam. If you don't fully understand how to design classes, write constructors, use access modifiers, and work with objects, you'll struggle on both the multiple choice and free response.

The big changes for 2025–26: Inheritance and polymorphism are gone. File I/O using Scanner and File is in. The exam now has 42 multiple-choice questions (down from 40, all single-select with 4 choices), and FRQ 3 is now explicitly ArrayList-only.

The Exam Format

The AP CSA exam is 3 hours long:

Section I — Multiple Choice (50% of score)

42 questions in 90 minutes
Single-select with 4 answer choices
Covers code tracing, logic, output prediction, and conceptual understanding
No calculator, no computer — just you and the Java Quick Reference sheet

Section II — Free Response (50% of score)

4 questions in 90 minutes
FRQ 1: Methods and Control Structures
FRQ 2: Classes and Objects (design a class from scratch)
FRQ 3: ArrayList operations
FRQ 4: 2D Arrays

Each FRQ tests your ability to write actual Java code by hand. Syntax matters, but minor errors (like a missing semicolon) usually won't cost you points if the logic is correct.

Study Tips That Actually Work for AP CSA

1. Write Code Every Day — Even Just 15 Minutes

AP CSA is a skills-based exam. You can't cram programming the way you might cram history dates. The more you practice writing and tracing code, the more natural it becomes. Use an IDE for practice, but also practice writing code on paper since that's what the exam requires.

2. Master Array and ArrayList Traversals

A huge chunk of the exam involves iterating through data structures. Make sure you can confidently write for loops, enhanced for loops, and while loops to traverse, search, filter, and modify arrays and ArrayLists. Know the difference between index-based and element-based traversals.

3. Trace Code by Hand

The multiple-choice section is filled with "What is the output?" questions. Practice stepping through code line by line, tracking variable values on paper. This is the single most important skill for the MC section.

4. Know the Java Quick Reference Cold

You'll have access to the Java Quick Reference sheet during the exam. It lists String methods, ArrayList methods, Math methods, and more. Don't waste exam time looking things up — memorize what's on it and how each method behaves.

5. Practice Writing Complete Classes

FRQ 2 always asks you to design a class. Practice writing classes from scratch: instance variables (private), constructors, accessor and mutator methods, and toString(). Make sure you understand encapsulation.

6. Learn to Read Code You Didn't Write

The exam will show you unfamiliar code and ask what it does. Practice reading others' code — understanding logic flow matters more than memorizing syntax.

Get Your Free AP Computer Science A Vocabulary Guide

We built a comprehensive AP Computer Science A Vocabulary & Key Concepts Guide aligned to the brand-new CED, and it's completely free.

Here's what's inside:

75 essential terms covering all 4 units of the new framework
Clear definitions written for students, not textbooks
Code examples and key details for every concept
Updated for latest CED: reflects the new 4-unit structure, removal of Inheritance, and addition of File I/O
Exam format breakdown with FRQ-specific strategies
Unit weight guide so you know where to focus

From int vs double to encapsulation to 2D array traversals — every concept you'll see on the exam is covered.

🎀 [Download the Free AP Computer Science A Vocabulary Guide]

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