I always thought that the Kellogs Special K advert which said, "For grown up people who'd rather not grow anymore.." really meant that it would stop you getting any taller. I loved the stuff but was always wary of stunting my growth. I'm 6'3" tall now (but fat)
A childhood belief about general

others believed things like this
- My dad told me that playing basketball makes you taller. Basketball players are tall, so I believed him.Anon
- i used to believe that if i walked in the rain i would grow taller.Anon
- i used to believe that you were suppossed to grow taller than your parents, and then when i didnt i was sad.— crysb83
- when I was younger , I used to soup made you grow taller — dark-titouan-du-55
- How could Baby Jesus be born on Dec 25th, get tall, grow a beard and then die, all by Easter. Whew!— Joe
- I used to believe that after I cut my barbie's hair, they will grow again. They've never grown :(— Duda