I'm organizing my studio for "Back to School" piano students. Their new books have arrived! In addition, I have a work table set up for doing music worksheets and especially coloring music pages. If you haven't seen me on Pinterest, here is one my boards, Music-Clipart-Coloring-Font
It seems many are doodling in their Bibles and adults are coloring more as a popular past time nowadays. You and your children may be interested in the following links for music coloring pages. Did I mention... they're all free! One of my favorite crafts is making the Stand Up Piano using three pieces of a straw!
Adult Coloring Pages
Cat Coloring Page
Christmas Holiday Practice
Garfield Music Coloring Page
Piano, Keys, and Notes
Stand Up Piano Coloring Page
Upright Piano Coloring Page
I've gotten tons of coloring pages from Melody Payne on Teachers Pay Teachers and also her site, http://melodypayne.com/
Perhaps you can use some of these templates for your studio, to share with your homeschool group or grandchildren.
Happy piano playing and coloring!