Music? Let’s wire up redstone note blocks to play your favorite song. Let’s talk about chords by playing multiple notes at once.
Music would be pretty difficult to teach. Note blocks only range to about two octaves. You’d be hard-pressed to teach things like counterpoint and chord inversions in just two octaves. Moreover, the instrument choice is also extremely limited, and you’d either have to teach them to read music ranging from F#3 up to F#5, and then there would be questions on how to read other notes. I’d not even open that door. I don’t know what age ranges you teach, but it would be a veritable Pandora’s box to try and introduce even basic music and music theory with note blocks.