Donald in Mathmagic Land was produced by Disney in 1959 to educate kids about math. After its theatrical release (and nomination for an Academy Award), the film was distributed to schools, and apparently children of the 60's learned some math from this trippy cartoon. I'd never heard of it until a friend posted a link on Facebook. My favorite exchange:

[Pythagoreans are playing music with lutes and such.]

Narrator: "Shh, it's a jam session."

Donald Duck: "Give us something with a beat!" [Donald starts playing an upside-down amphora that sounds suspiciously like bongo drums. The Pythagoreans begin to get funky.]

Narrator: "So from these eggheads, the Pythagoreans, with their mathematical formula, came the basis of our music today."

[White guys playing big-band jazz are shown.]

So while I disagree with some of the specifics* shown in this thing (Pythagoreans invented jazz?), it's kind of a hoot -- and there is genuine educational content here. Check it out (in three parts):

* = According to Wikipedia, the value of Pi is incorrectly reported early in the film:

Despite this being a mathematics educational film, a character incorrectly recites the value of the mathematical constant pi. The character states, "Pi is equal to 3.141592653589747, et cetera, et cetera, et cetera". The correct value of pi (to the same number of digits) is actually 3.141592653589793.

I had no idea -- I only memorized Pi to 11 decimal places.