My dad once belived, ~1937 or so, that there was an operator for electricity just as there was an operator for the telephone. So, ne day he decided to play a trick on the electricity-operator by screwing a coin into a lamp socket. Not only did it blow a fuse, but he got a bit of a shock too. Turns out the operator had a trick for him too.
A childhood belief about around the house

others believed things like this
- I used to think that in the song "Smooth Operator" they were saying "Schooooooool's not forever!"— Steph
- When I was a kid I was completely convinced that Sade's "Smooth operator" was "Ooh of the red eye".— Brookstar78
- I used to believe electricity came from lightning.Anon
- i used to believe lava and water made electricityAnon
- i used to believe that the no outlet signs meant that noone in that section of the street had electricityAnon
- I used to believe that electricity was manufactured in a factory in a place called 'Electriz City'.— Sally