Unit 03

Class Creation

Stop 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.

10–18% of the AP Exam~20–22 CED periods~10–12 blocks here9 topics

AP Computer Science A · members' unit

Class Creation is behind a locked door

Units in AP Computer Science A are for people taking the course. Getting in takes a link or a key — signing in on its own doesn't do it.

What's in this unit · 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 drills

1 Sign in

With your school Google account. This is how your work reaches the gradebook — it doesn't open the unit by itself.

2 Get in

Open the class link your teacher posted — that's the usual way, and it enrols you on the spot. Or paste an access key if you were handed one.

A key unlocks this browser and keeps your progress here; signing in keeps it with you across devices. Either way the key itself is only ever checked as a hash. Manage all of this on your account, read what signing in stores, or go back to AP Computer Science A.

Sources

  • College Board — AP Computer Science A Course and Exam Description, Effective Fall 2025