The app works with bite-sized puzzles and quizzes, so you can breeze through a couple lessons each day when you have some spare time. You log in with your Google account, are walked through basic coding definitions, and then you start the exercises. The further along you get, the more complicated the puzzles become. The app will also ask if you’d like to set a practice schedule and get reminders — daily or a couple of times a week — so you don’t lose any recently learned skills.
Grasshopper begins with what it calls “The Fundamentals,” which includes things like calling functions, variables, and strings. Every time it introduces a new concept, you get several puzzles for practice. For example, an early puzzle dealing with shapes asks you to draw the French flag. It shows what the solution looks like, and then below is a space where you can tap on blocks of code to build a script that replicates it. Later courses cover animations and more complex functions using the well-known D3 library.
Grasshopper is free to download from both Google’s Play Store and Apple’s App Store.