When I was 6 I used to believe that my "exercises" lived in a door in my leg and before I did any sport I had to open the imaginary door and afterwards I had to put them all back.
A childhood belief about general

others believed things like this
- My sibs and I thought that the screen door was called the "scream door" so Mom could yell at us through it. — Kyle
- i used 2 believe when i left my closet door open at
night a skelleton would pop out and wave at me— bex - I thought if I left the door open too long, a dog would come from the cupboard in the washroom and eat me
Anon - I used to think that 'Child Locking' only worked on children and that older people could still open the door.— Anonymous Whistleblower
- i thought there was a door in the back of the tv and if you wanted to be on tv you just walk in— fred
- I used to believe there was a secret door to the gremlin world hidden under my bed— Mel