I usw=ed to (still do!) believe that you should take your coat off when getting into a car on a cold day, so that you can feel the benefit of it when you get out. The same goes for entering houses or shops.
A childhood belief about cars

others believed things like this
- I used to think small furniture shops were basically cottage converted charity shops.Anon
- I used to believe that a stranger was a man with an X on his coat— Gabe
- I used to believe that thunder was aliens entering the atmosphere, and lightning was them firing lazers at us!— Zeepoo-zoop
- i used to believe shopkeepers lived in their on shops— Anonymous
- I used to think all money paid for goods at shops went to charity.— Tim
- When I was little I thought
body shops were places to
work out.— ginny