I believed until a worryingly late age that there were 3 one O'Clocks in the day, based on what I had heard people say: there was one in the middle of the day, one late at night, and one very early in the morning.
A childhood belief about general

others believed things like this
- I used to believe that when the sky was pink, late at the afternoon, the angels made cookies!— Bella
- Oasis - Don't Look Back In Anger
"Oh, Harry can't mate
He knows it's too late
As he's stalking, oh my..."— Santa Puncher - I used to think that girls' anuses were green. I remember thinking that as late as high school.— Jack
- I used to think that my teacher lived at school until she came to school late one day. I was shocked!— Wow, you have a life?!
- When I was younger, I believed that times tables in maths were kids sitting at tables staring at clocks!Anon
- Based on that memorable scene from the "Wizard of Oz," I used to believe that people died from shrinking!— Julie