I used to think that the characters on cartoons are actually puppets. I wouldn't believe my uncle when he told me that they were drawn.
I used to think that if I don't leave the bathroom after brushing my teeth in 2 minutes, I would be locked in there forever. That explains my bad oral hygiene.
A childhood belief about cartoons

others believed things like this
- I thought live-action films were very, very well-drawn cartoons.Anon
- I thought "Angel of the Moring", by Juice Newton said "just brush me teeth before you leave me"!!!Anon
- I used to believe that eating burnt toast would make your teeth whiter and would brush your teeth for you.— Natasha
- I used to believe that if I didn't brush my teeth at night, ants would crawl into my mouth and eat my teeth.Anon
- I used to think that tampons were meant to absorb women's urine so they wouldn't have to go to the bathroom.— Koyaanisqatsi
- Until I was about 8 I believed that your back teeth keep growing in until you have a full circle of teeth.Anon