When I was 6 years old, I somehow got the concept that counting was infinite - you could always go one higher. Naturally, I concluded that EVERY WORD is a number! So cow, pencil, and airplane were numbers, I just didn't know where they went in the whole scheme of things. This still makes sense to me.
A childhood belief about counting

others believed things like this
- When I was little I thought you could get arrested if you accidentally skipped a number while counting.— Hailey
- As a kid I used to believe that when you sharpened your pencil, the eraser on the pencil grew.Anon
- I used to believe that numbers had gender, that the odd numbers were boys and even numbers were girls. — Evelyn
- I thought the lines in the sky left behind by airplanes were "sky scrapers". Makes sense.Anon
- I used to believe that after the number "ten" came the numbers "tendy-one, tendy-two..." etc.Anon
- As a child I used to think that the sea was infinite.Anon