I used to believe that the "We All Live in a Capital I" song from Sesame Street was a conceivable situation. I also thought that those big letters and numbers they had as props were something that you were supposed to have around in real life, and didn't understand why I never saw a giant blue B sitting on a brick wall...
A childhood belief about tv shows

others believed things like this
- Pink Floyd- Brick Wall.
I used to believe it was "we don't need no fart control" in the second line there.— Norwegian Dude From Kopervik - I used to think the line in Pink Floyd's Another Brick in the Wall was "No dogs allowed in the classroom."— Gretchen
- I didn't understand about boiled eggs until my Mum explained I wasn't supposed to eat the shell as well.— Chris
- I used to believe that Paris was the capital of London and Italy was the capital of France.Anon
- I used to believe that “Emo” was related to Elmo from Sesame Street.Anon
- I seriously used to believe that Bert from Sesame Street lived in my closet and that he was going to kill me.— Liz