As a child (In UK), I believed that all cars had to drive on the left, except cars that were coming the other way. Of course Police cars and Ambulances were allowed to drive down the middle of the road.
A childhood belief about cars

others believed things like this
- I thought the no overtaking sign meant that red cars cannot drive by black cars.— Helen
- I used to believe that self drive cars actually drove themselves!Anon
- I used to believe that cars grew and that our car would grow to big to go under the McDonalds drive-thru.— Mary Ellen
- i used to believe people were put in coffins because they were special cars that could drive you to heaven!— jym
- I used to believe that the "cruise control" button in cars meant that the car could drive/maneauver itself.— Myriam
- I thought small cars grew up to become big cars— carhugger