When I was little I always heard people use the phrase "car pool", so when I saw a car with a cab on the back, I thought you were supposed to fill it with water and invite people in.
A childhood belief about swimming pools

others believed things like this
- I used to believe that your tap water came from the swimmimg pool.— Mimi
- When I was little, my dad told me that if you pee in the pool the water will turn purpleAnon
- i used to think water towers were houses for really tall people. I thought they had big heads to.— Alyssa
- I was born brunette with brown eyes and dark hair, i thought people with blue eyes, had water in them.Anon
- That an undertow was a giant toe under the water that grabbed people and pulled them under.— mikita Jones
- I used to think that a carpool was one of those bug, long limosine's with a pool all the way in the back.— Annie