I used to think that a lady werewolf was under my bed when I was six well into my 6th grade. To this day I still can't sleep with any limbs hanging over the sides, even knowing better.
I thought it was because I remembered a scene in a movie called "Werewolf of London" where a woman discovers blood under her bed and a werewolf hand snatches at her and she wakes up. Someone was trying to make her believe she was a werewolf. No such scene exists in that movie, though. And I still haven't found out if that scene was actually in a film or not.
A childhood belief about under my bed

others believed things like this
- i used to think that i was a werewolf and that at night i played poker with the grim reaper— mike
- Based on that memorable scene from the "Wizard of Oz," I used to believe that people died from shrinking!— Julie
- I used to beleive that in order to rewind a film the actors would have to re-act the whole movie backwards. — movies backward
- I used to believe that guns shot out blood because everytime somebody shot a gun in a movie you saw blood.Anon
- when i was little i believed that when we watched a movie people had to act the movie all over a gen.
— Emmer - I used to think that a movie is made in realtime. I tought that a 2 hour movie is made in 2 hours.— Alexander