When i was little (like 2-3), I didn't know the names of any numbers over 10, but I knew that 11 and so on was 10 plus a number, so I would call 11 "10 dee 1" and so on. Everyone was really confused until I explained it to them. They soon set me straight.
A childhood belief about getting older

others believed things like this
- I used to believe that numbers had gender, that the odd numbers were boys and even numbers were girls. — Evelyn
- I used to believe that after the number "ten" came the numbers "tendy-one, tendy-two..." etc.Anon
- I used to believe that north was always straight ahead. I could never face south, but I knew it was behind me!— Bruces
- when i was little i believed that your social security number was the number you were born on the earth — christine
- I used to think making straight A's in school was literally writing A's straight. Anon
- My father used to call soya sauce "monkey blood". I didn't even consider tasting it for years!— Me