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The Destination for Beginners, Students, and Teachers of Java

Try out Modern Java Now

The Java Playground allows you to run snippets of program code to see the results. The way the Java Playground works, no class or main method is required. Just hit run below!

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Been here before? Looking for something new to learn? Try these!

Pet Recommender

Determine the best pet to recommend based on whether you have a backyard and the amount of time you have to spend.

Esports Tournament Qualifying and Seeding

Determine whether an Esports team qualifies to participate in a tournament or not.

Introduction to Algorithms Practice

Write sequential algorithms for every day activities.

Learning Java Has Never Been Easier

Videos to get you started

AP CSA in 30 Weeks (2026) | Week 7 | Algorithms

In this week’s lecture, we cover AP CSA Topic 2.1 on selection and repetition algorithms.

Week 8 | Boolean Expressions & if Statements | AP CSA in 30 Weeks(2026) | Topics 2.2 and 2.3

In this week’s lecture, we cover AP CSA Topic 2.2 and 2.3 on Boolean expressions and writing if statements.

Episode 3 | Making Abstract Concepts Concrete | Class Constructors

We're exploring class constructors using marshmallows, M&Ms, and pretzels to create our very own MarshmallowMan objects!

Hands-on Algorithms | Episode 4 of Making the Abstract Concrete

We look beyond the peanut butter and jelly algorithm to other hands-on ways students can learn to write out and test algorithms in real-life.