Josh (9y) is playing on his electric keyboard. It has all sorts of songs in it's memory bank, and lately he's been fixated on Pachelbel's Canon. The keyboard also simulates all sorts of instruments. His favorite lately is the harpsichord.
So I pulled up a recording online of Pachelbel's Canon performed by a string quartet. Then he wanted to hear it on a real harpsichord, so of course we did that. Then he wanted to see how a harpsichord worked, how it is different from a piano. Next I explained to him why it was called Canon "In D", and showed him a quick rundown of scales.
Satisfying his curiosity and filling the house with beautiful music- Double win. It isn't always this mess-free and relaxing. ;)