When I was little I believed that the magical-seeming abilities of adults --card tricks, memorizing directions to a strange place at one fast hearing, lifting heavy things, etc.-- all came from tests of inner will and self-discipline (though I didn't yet have those words, I had the concept). I believed that doing anything that was hard would make me better, not just at whatever it was, but at all things, and that the harder a thing was to do, the sooner I'd be able think really fast and tell long jokes properly and do all the other grownup things.
My mother taught me to read as I was learning to talk. When I was four or five I read about eclipses in a children's science book. It plainly said you should never look at the sun-- which intrigued me. Later, playing out in the alley, I gritted my teeth and held my eyes open with my fingers and stared at the sun for a predetermined count of ten. Then, after the spot went away enough so I could see to move around, I went in to where my mother and grandparents were and told them. I was so proud and they were so horrified. "Oh, no, honey! /Never/ look at the sun!" But it was right there, available.
A childhood belief about special powers

others believed things like this
- when i was a kid i believed i could make things happen just by snapping my fingers like in mary poppins!!Anon
- i used to believe that parents do things to make there children happier. well i was wrong. — Emma C.
- I used to believe God had a pet tortoise. There was a hymn we sang that went "Great things he hath taught us"— Lozza
- I used to think that the things you get in your teeth were called feelings.Anon
- When I was little i thought that seconds were so fast that you couldn't count them.— Baby
- I thought farting was magical wind, and if you did it loud and hard, you would be able to move yourself.— Blake