I knew that the earth was spherical for as long as I can remember... but I do remember a time (until I was 4 or 5) that I believed that people on the other side had to hold on to these rungs when they moved from building to building to keep from falling out into space. I thought the houses were made so that the people walked on what we think of as the ceiling... with their feet facing the sky.
A childhood belief about physics

others believed things like this
- I used to think the Empire State Building was called the "Ten-past-eight building".— Alex
- I believed dinosaurs made the mountains whenever they walked the earth.— Tammy
- I used to believe that the large building/skyscrapers that made smoke were "cloud machines"Anon
- When I was a kid I thought babies where made when people hold hands and kissed nude...— Ryan
- When my daughter was 3, she saw a cat using a litter box. She thought it was building a sand castle.— Debbie the Bad Swimmer
- I used to think that when you moved, you SWITCHED houses with the person who moved out.— Sheippe