One day while sitting in the back of my mum's car (aged 6 or so), I somehow invented the belief that if we stopped on a bus stop for any reason at all, we'd turn into a taxi, have to take someone wherever they wanted to go, and I'd be late for school. This was quite a fearsome problem, given rush-hour traffic, and that being late was SUCH a taboo...
A childhood belief about cars

others believed things like this
- 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?!
- 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 believe that when the sky was pink, late at the afternoon, the angels made cookies!— Bella
- I thought if 3 cards stopped at a 3-way stop sign then they had to stop forever until Christmas.Anon
- I used to believe that God controlled the traffic lights. He would decide when it was everybody's turn to go.— Amanda