MamaT posted a link to Pachelbel's Canon, a piece Sam is currently learning for a future piano recital.
Here's my response to MamaT:
Dear MamaT,
Thank you! You just contributed to a homeschool lesson about why it's important to practice your piano. Sam loved that piece and he's learning it on piano now. I pointed out to him that once he learned enough piano playing and theory he'd be able to build his own Canon.
"And my own music?"
"And your own music."
"And other people would play it?"
"Yes."
Thanks again MamaT.