I used to think that if you unscrewed your belly button (naval), your bum (butt) would drop off.
Also I had a teacher who used to yell at unsuspecting kids in the class "Don't pick your nose, your eyes will drop out". Truely terrifying. When I used to see those kids who had spectacles with a plaster over one of the lenses, I thought that they had been picking their noses too much.
A childhood belief about picking my nose

others believed things like this
- my gandma said that if i picked my nose my eyes would drop out— Lesley
- My kids believe if they pick their nose their butts will fall off!— wendy
- My wife used to tell our kids that if you pick your nose your brains would fall out— grampy
- i used to believe "eaves drop" was actually "ears drop"— sophie
- When I was a kid my dad told me that if you unscrewed your belly button your bum would fall off.— Ann
- i used to believe that if you poked yerr belly button yerr butt would fall off.— jordy