I've told the story before: as a kid, I went to Catholic school run by nuns. I was born left handed, so the nuns would hit my hand with a ruler multiple times every time I picked up a pencil with my left, telling me I will not write with the "hand of the devil".
Nice campus, though... a school for rich kids... lots of donations from parents of kids who were failing miserably but miraculously passed finals and went on to the next grade.
They did the same thing to my uncle, who ended up having absolutely terrible handwriting because of it. My father, who was six years younger, is also left handed but wasn't forced to write right handed, and he has fantastic penmanship.