I used to think that the "wind chill factor" was the "windshield factor" that was somehow derived by measuring the temperature of the windshield when a car was going really fast.
A childhood belief about cars

others believed things like this
- I used to believe that if you turned the thermastat temperature above 70 degrees that everything would melt.Anon
- I used to believe that trees made the wind, but its the wind that blew the trees!— victoria
- I used to believe that the wind was caused by trees so you could stop the wind by getting rid of trees.— Nira
- I used to think that the tree branches moving was making the wind, not the wind making the tree branches move.— Jenny
- I used to believe that I could control the wind.Anon
- i used to believe trees made the windAnon