When I was about nine, my 5th grade class had a very vague presentation on reproduction. We knew the basics of sex, but we were not told about ejaculation or sperm. Not wanting to ask, my friend and I debated for a while and came to the conclusion that a man pees into a woman to get her pregnant. For quite a while after this, we were scared to use toilets after boys, and decided that we would never have sex because it was so disgusting. A few years later, her older sister cleared things up for us.
A childhood belief about sex

others believed things like this
- I use to believe that the man peed in the woman to get her pregnant. Didn't know about sperm until sex ed. — das
- I never knew why boys had to lift up the toilet seat...until my friend told me that boys had bad aim.Anon
- a friend of mine thought that you could get pregnant by swallowing sperm. Ha!Anon
- I used to think boys went "number two" with their pee pees. Anon
- I used to beleive that if you got married getting pregnant was just a random event. I was so scared of boys!— me
- a friend of my little sister's had 4 older brothers, so she thought that when you got older you grew a penis!Anon