When I was a kid I would always see these little yellow lights at my window. I was convinced that my neighbors across the street were aliens and were pointing lasers at me to collect data.
Much to my dismay, and my mother's hilarious pleasure, they were just fireflies.
A childhood belief about aliens

others believed things like this
- I used to be convinced that there were bald-headed beige aliens outside my toilet window.— Phil
- Street signs with the upward pointing arrow was for airplanes. — Tammy
- i used to believe that red yellow and green meant "ready, set, Go!" on traffic lights..— cabagona
- I used to believe that the yellow light in traffic-lights meant Go Faster!— M. L. E.
- When I was little I thought that the street lights went out after everyone went to bed.— supercalifragilisticexpialidocious
- i used to think next door neighbors were "next store neighbors"Anon