When I was little, my brother convinced me that the third pedal on a car (the clutch) actually made traffic lights turn from red to green. He would wait until the light was about to change then press the clutch. Sure enough, the light would always turn.
I didn't figure this one out until college. Sad, I know.
A childhood belief about cars

others believed things like this
- My dad could change a traffic light from red to green using our garage door opener.Anon
- that the green traffic light turned blue when it was off— Kriket Evens
- When i was little i always thought there were little men inside the traffic lights changing the light— Kiley
- I used to believe that the yellow light in traffic-lights meant Go Faster!— M. L. E.
- I used to beleive that little drawf men were inside each traffic light, making them change colors. — alisha
- I used to believe that God controlled the traffic lights. He would decide when it was everybody's turn to go.— Amanda