When I was in junior high school I thought that shampoos "for dry hair" gave you dry hair and shampoos "for oily hair" gave you oily hair. I always bought the shampoo for dry hair and didn't understand why anyone would ever buy the shampoo for oily hair... I mean, who would want oily hair?
A childhood belief about bathrooms

others believed things like this
- I used to think that if i put conditioner in my hair before the shampoo my hair would fall out.— Jerry Moe the Gimp
- I used to think that everybody's hair was black and if you had blond hair, you dyed your hair.— ~_~CoolKid93_~_
- When I was little I thought that dying your hair means you kill your hair.Anon
- I used to hold my hand over my hair whenever i left the house and it was windy incase my hair blew away— lisa
- I used to believe that you could curl your hair by twirling a strand of hair wrapped around your finger— Anonymous
- I believed that if you ate a piece of your own hair, a new strand of hair would grow on your head.— Ryo