I used to think "forced air" heating was "four stair" - somekind of multilevel system.
A childhood belief about around the house

others believed things like this
- when i was very little, i thought that all girls must do ballets, and that i was lucky who wasn`t forced to. — little miss from norway
- I used to believe that I invented the X Y coordinate system.Anon
- I used to believe GPS stood for Ginormous Processing System. — Babre
- when I was small I always thought that the solar system ended, and then it was just white paper after that— sparrow
- When I was younger, my brother told me the police had an infra-red system and could see into everyones house.— Clare, Ireland