Embrassing as this is I still believed it up to about 15. When we did geography exams (this is in the UK)you sometimes got given a map to work from. At the bottom there was a grid of 4 blocks of colour. If one of them hadn't printed properly it meant you might not get some of the details on the map and you might fail. Beside this it said @If 4 colours are not shown, please return the map to the invigilator@ I used to think the invigilator was the machine that printed the maps, not the teacher sitting at the front.....
A childhood belief about classes

others believed things like this
- I used to believe that ATMs actually printed out the money fresh every time. — Kitty B
- I used to believe that Internet banking printed money out of the printer in our home like an ATM. Anon
- When I was young, I really used to believe that 'R.I.P.' (on a gravestone) meant 'Return If Possible.'— Colin
- I used to believe that when you had cancer, your bottom would be in front instead of in back. Anon
- I used to think my belly bottom was my "front butt" lol i know...stupid!— Megan
- i used to believe that our ansering machine was the washing machine and that it could talk
— tamara