I'm 15, and I was just browsing the site. I feel insanely stupid, because I came across this one belief that states that they believed chickens and hens were the same breed of bird, and that they were always female, and that cocks were always male.
I too believed this, until about two minutes ago..
A childhood belief about birds

others believed things like this
- I believed that chickens pooped eggs (male and female)— WHAT-A-Doodle-WHO??
- I believed that all cats were female and all dogs were male. — Biologically confused
- I used to think that to desex an animal meant to turn it from a male to a female or female to male.— Phil
- I used to think that turkeys were male chickens. Don't know why, but I did.— Felicia
- I believed that the breed of dog called Boxer was called that because they could stand up and box.Anon
- I used to believe all cats were female and all dogs were male.— Sabby