See the structure of music.

Figure out Music visualizes music theory on real instruments and drills you on it. The core idea runs through every page: the twelve notes split into two whole-tone families — F G A B C♯ D♯ and C D E F♯ G♯ A♯ — and every major scale takes three notes from one family and four from the other. Once you can see that split on your instrument, key changes stop being abstract.

Everything is keyboard-driven (hotkeys are shown on the controls, press ? on a practice page for the full list), works with a MIDI foot pedal, and the pink marker is always the note to find.