My favorite school movie as a kid

Donald Duck in Mathemagical Land.  Must have seen this 15 times in school over the years; probably every time a math teacher was hung over and didn't feel like trying to teach us brats algebra or something. It's on YouTube for now, but who knows how long Disney will allow that. Taught me everything about billiards I ever knew.  Some bogus material on Golden Ratios in early Greece, but generally very cool at showing how math is in everything in everyday life. I love the Disney narrator, Paul Frees. What a voice.