I used to believe "I Want Candy" was actually "I'm A Kidney", especially since they played it in PE/health class at my school.
A childhood belief about misheard lyrics

others believed things like this
- I thought if you took some candy and buried in the yard, you would grow a candy tree.Anon
- I used to beleive that if you swolled a tablet whole you would get kidney stones— kaye
- When I was a little kid and fell down and skin my knee, I used to think I was skinning my kidney.— G. Dedrick
- I used to think that people who donated their kidneys were doing it for steak and kidney pie.Anon
- I used to believe that a 'soul' was an organ of the human body, such as a kidney or lung. — Grace
- i used to belive that kidney beans were bean shaped things that grew in kidneys... untill yesterday — Jokey