I remember being taught in Elementary school that in the time of Colombus most people thought the Earth was flat. That's a myth. Eratosthenes (an ancient Greek) knew the circumference of the earth to within 1.4%.
One reason I like math is, even if it's hard, at least your teachers only teach you true things.
I recently found out that the mass suicide of lemmings is another myth, and was in fact perpetuated by Disney's murder of lemmings! Snopes has the story. (Be warned that I have FlashBlock installed, so I am not sure what advertisements this site normally displays.)
