Did you have any silly misconceptions about the world when you were younger?

When I was little I believed that little girls grew up to be men and little boys grew up to be women, because that's what my cousin told me.

My boyfriend told me that when he was little he got really frustrated using a straw, because he didn't realize you had to suck the liquid up. He saw people using straws and it just looked like the liquid was getting pulled up the straw on its own.