Tutorials

Seven small projects, meant to be done in order. Each one introduces one new idea and reuses everything before it.

All of them run right here in the browser, with no downloads at all: every picture and sound they use is built into Scratch for Java. The sixth shows at the end how to use pictures of your own.

	Chapter	What is new
1	Your first program	A sprite, a costume, and run()
2	Make it Walk	Several costumes, timers, animation
3	Catch the Coins	A score, random numbers, collisions
4	Red Light, Green Light	Messages between sprites
5	Guess the Number	Asking the player something
6	Bouncing Hedgehog	A whole game on your own, and your own pictures
7	Dodge the Rocks	A window with a title, a game and a game over screen

Each chapter ends with Things to try: small extensions, each with a hint and a solution you can unfold. Stuck? It doesn't work! has the most common mistakes, and the cheat sheet shows which Java line replaces which block.

For teachers

Every code block on these pages is compiled as part of building this site, so nothing on them can quietly stop working. For teachers has a plan for the unit, with the learning goal and the typical stumbling blocks of each chapter.