AP Computer Science A 7-Day Cram Plan

You have one week to lock in AP Computer Science A. This plan dedicates one day to most units, with focused FRQ practice and a full mock on the weekend.

Commit 5 focused hours per day. Use the Java Quick Reference (provided on exam day) even during practice — you won't have it memorized, and that's okay.

Study Schedule

Monday: Primitives & Wrapper Classes

Review checklist (90 min)

• Primitive variable declaration and initialization.
• Integer division: 7 / 2 = 3 (not 3.5).
• Modulo: 7 % 2 = 1.
• Math.abs(), Math.max(), Math.min(), Math.pow().
• Math.random() returns a double in [0, 1); multiply and cast to get an int range.
• Wrapper classes: Integer, Double, Boolean.
• Autoboxing: Integer x = 5; (wraps automatically).
• Unboxing: int y = x; (unwraps automatically).

Practice (3 hrs)

• Write a method that generates a random int between 1 and 100 (inclusive).
• Write a method that takes two ints and returns the max.
• 10 multiple-choice on primitives and integer division.
• 1 FRQ-style: write a method using Math.random() and modulo.

💡 Exam trick: On the calculator section, you can use Math.random() in code; on non-calculator, interpret it conceptually.

Tuesday: Using Objects & String Methods

Review checklist (90 min)

• String declaration: String s = "hello";
• .length(), .substring(start, end) (end is exclusive), .charAt(index).
• .indexOf(substring) returns the index, or -1 if not found.
• .compareTo(other) returns negative, zero, or positive (lexicographic order).
• .equals(other) and .equalsIgnoreCase(other) for comparison.
• Never use == on Strings — it compares object references, not contents.
• String immutability: s.substring() does not modify s.

Practice (3 hrs)

• Write a method that counts how many times a character appears in a String.
• Write a method that reverses a String.
• 10 multiple-choice on String methods.
• 1 FRQ-style: parse a CSV line by finding .indexOf(',') and using .substring().

⚠️ Trap: .substring(0, 3) on "hello" returns "hel", not "hell". The end index is exclusive.

Wednesday: Boolean Expressions & Conditionals

Review checklist (90 min)

• if, else if, else structure.
• Relational operators: <, >, <=, >=, ==, !=.
• Logical operators: && (AND), || (OR), ! (NOT).
• Short-circuit evaluation: a && b stops at a if a is false; a || b stops at a if a is true.
• De Morgan's Laws: !(a && b) is (!a || !b).
• Nested conditionals and if-else chains.

Practice (3 hrs)

• Write a method that determines if a number is even, odd, or prime (for small numbers).
• Write a method that grades based on a score (90-100 = A, etc.).
• 10 multiple-choice on conditionals and short-circuit evaluation.
• 1 FRQ-style: write a method with compound conditions.

Thursday: Iteration & Writing Classes

Review checklist (90 min)

• for loop structure: for (int i = 0; i < 10; i++).
• while loop: condition checked before each iteration.
• Nested loops and loop control (break, continue — though continue is rare on exam).
• Enhanced for-loop: for (int x : array) iterates over each element.
• Writing a class: fields, constructor, instance methods, this keyword.
• Instance variables vs local variables; scope.
• Static variables (shared across all instances).

Practice (3 hrs)

• Write a complete class Student with a constructor, a name field, a grade field, and a method to update grade.
• Write a method with a nested loop (e.g., print a multiplication table).
• 10 multiple-choice on iteration and class design.
• 1 FRQ-style: design a simple class (Part A).

💡 High yield: FRQ Part 1 often asks you to write a single method; Part 2 asks you to write a complete class. Know the exact structure.

Friday: Arrays & ArrayList

Review checklist (90 min)

• Array declaration: int[] arr = new int[10];
• Access: arr[i] (0-indexed).
• Common algorithms: find max, find min, sum, count matches, search, reverse, swap.
• ArrayList: ArrayList<Integer> list = new ArrayList<>();
• .add(element), .remove(index), .get(index), .set(index, element), .size().
• Enhanced for-loop with ArrayList: for (Integer x : list).
• Remove during iteration pitfall: always remove from the end backwards, or use a separate list.

Practice (3 hrs)

• Write a method that finds the index of the maximum element in an array.
• Write a method that removes all multiples of 3 from an ArrayList.
• Write a method that reverses an array in-place.
• 10 multiple-choice on arrays and ArrayList.
• 1 FRQ-style: array/ArrayList traversal problem (Part 2 or 3).

Saturday: 2D Arrays & Inheritance

Review checklist (90 min)

• 2D array declaration: int[][] grid = new int[rows][cols];
• Access: grid[row][col].
• Row-major traversal: loop rows (outer), then columns (inner).
• Inheritance: class Dog extends Animal { } — Dog inherits fields and methods from Animal.
• Constructor: super() call to initialize parent fields.
• Method overriding: same signature, different implementation in subclass.
• Polymorphism: Animal dog = new Dog(); — dog is an Animal, but overridden methods use Dog's version.
• The Object class: every class implicitly extends Object.

Practice (3 hrs)

• Write a method that sums all elements in a 2D array.
• Write a method that finds the max in a 2D array.
• Design a class hierarchy: Animal (superclass), Dog and Cat (subclasses) with overridden methods.
• 10 multiple-choice on 2D arrays and inheritance.
• 1 FRQ-style: inheritance and polymorphism.

Sunday: Recursion + Full Mock Exam

Review checklist (60 min)

• Base case and recursive case.
• Recursive helper methods: pass an additional parameter (e.g., index or accumulator).
• Common patterns: factorial, Fibonacci, sum of array, count occurrences, binary search.
• Tracing a recursive call: write out the call stack by hand.

Practice (4.5 hrs)

• Trace 3 recursive methods by hand (5-10 steps each).
• Write 2 recursive methods from scratch.
• Full 3-hour timed mock exam: mix of multiple-choice and FRQs.

🎯 Mock exam mindset: Treat this as the real thing. Use only your calculator, no notes, strict timing.

Post-exam tonight

Review your mock: which topics cost the most points? Which FRQ patterns did you struggle with? Spend 30 min on your weakest topic before bed.

Related guides:

• 3-day cram plan
• FRQ practice guide
• Last-minute review