My friends and I (male) believed at school that a woman's breasts became bigger when fondled by a man. So when we saw a large-breasted lady we sniggered- we knew what SHE'D been up to!
My wife told me this was not true about two years after we married.
I'm still not convinced she's right.
A childhood belief about rude bits

others believed things like this
- I believed that when you got married (the wife) you didn't have to work. Boy, was I fooled. ha ha ha— Patty
- i used to beleive when you drank milk your breasts would get bigger so i used to look down at them afterwordsAnon
- i used to think that the pope was married but also i thought howcome her wife never appeared on TV— jp
- When we were young, we used to call a woman's breasts, 'Hum Hums'— Steve Haughton
- I used to believe that a widower was a guy who killed married husbands to make thier wife a widow— Jessica
- I used to believe that an erection only occured after a male was married and that it was a permanent thing.Anon