I have been a Sandra Boynton fan for years. Our now-college-sophomore daughter can still recite "Moo, Bah, La la la" by heart with all the sounds, and singing and rhythms we used, every time. I was not a math teacher when "Moo, Bah, La la la" first crossed our paths, but I am now, so when I saw Boynton's Geometry Lesson cartoon, I was smitten. She had me at hippopotenuse.
Whimsical, Mathematical, Perfect.