I used to believe you could parachute with a bin bag. I realised my painful mistake upon landing but tried again anyway... a few times, just to make sure.
A childhood belief about physics

others believed things like this
- Yesterday I realised that invisible ink doesn`t make me invisible.— Jonathan Eleven years old
- I used to beleive that a catacism(spelling?) was an extremely painful Christian version of a bris.— Mike
- I used to think that "One, two, three times a lady"
was: "one, two, three times related"Anon - I used to think that 7-Up was called "Zup" until I realised the "Z" was actually a Seven!— Vic
- i used to think that franch was actually swearing !!!! until i realised it was just like english lol :PAnon
- i used to believe that stars really were star shaped, i realised at the age of 34 how wrong i was.Anon