when I was around 5 or 6 I had an imaginary elementary school class...they all had distinct personalities and went everywhere with me. (Ruby was the bad one, Penelope was the good one, Tommy and Toby were twins, Annika and Clarence were in wheelchairs, etc.) There were approximately 15 in all. I would write up lesson plans, administer severe discipline, and carry on full conversations with them in public places. I was a weird kid. Oh, and, of course, their music teacher was John Lennon. :)
A childhood belief about imaginary friends

others believed things like this
- I used to think my elementary school gym teacher's name was "Jim Class".— Brandon Campbell
- I used to think that Lenin and John Lennon were the same person.— Melanjolly
- I used to think that the Beatles broke up when John Lennon died.— Shirley B.
- When I was in elementary school I use to think that teacher lived at school at their desks all year long.Anon
- I thought that Tommy Lee (the singer) and Tommy Lee Jones(the actor) were the same exact person.— Glowworm
- My music teacher once said that music in an electrical piano was made by little tiny men that lived inside it.Anon