Wonderful! I recently did something similar to teach kids to program a game (in german): https://game.bbz.cloud/topics/04_collisions To get the step-by-step code building, you can add comments to individual lines of example source code to tell them when they should appear (and optionally disappear): https://github.com/bbz-biel-informatik/jsgame/blob/master/04... It currently works for JS, HTML and CSS.