I guess this would fit into this topic:
When I was a kid, I thought that the voice on the phone when you called the time was just one women who had to sit in a little room and answer that phone all day and night.
A childhood belief about telephones

others believed things like this
- I always thought that my relatives were really tiny, and inside my phone when I talked to them on the phone.Anon
- Yep I thought the Zephyr song was fly away on my cell phone— Jenny
- i thougt robers could shoot into the phone and the bullet would come through and hit me— knowledge
- When I was little I used to believe that all old women were called Betty!!— Katie
- I used to believe that every country in the world had the same time. Guess I didn't consider time zones eh?— what are time zones again
- Before I went to a planetarium for the first time, I thought it was just a room full of plants. Anon