I used to believe that "car pools" were cars with pools in them, like in the rock videos.
A childhood belief about swimming pools

others believed things like this
- I used to think that the pools was a swimming competition.— Matt
- I used to believe that sharks lived under the pools where the air vents were. — Carol
- i used to believe that pools had underwater doors that sharks were going to swim out of.— marky
- my Dad told me ice rinks were defrosted every evening and turned into swimming pools— neil
- My friends and I used to believe that if you planted a rock, it would grow a rock tree. Anon
- I used to believe the the Elton John song, "Crocodile Rock" was about a Crocodile, named Rock.Anon