My son, just shy of 6, wanted to DM a game of D&D like his dad. Yesterday, he got his wish!
I tried to rally the troops, which was entertaining of itself. Jeremy in particular, asking me "What system will it be?" "What about character sheets?" as if it were going to be anything other than freeform gaming. Maybe he had my boys mixed up? My 12 year old is also hoping to DM a game soon, too, and it will likely have some more structure.
Dean and Denis were free, and of course me, too. We created characters! I was a big fat wizard (Stevie basically gave me this character), Dean was a sentient jack-o-lantern, and Denis was a kung fu dragon-man.
The session involved us stopping rampaging ass-goblins by cleaning them, interacting with bizarre NPCs, lots of "home shopping" where Stevie would tell us that there was something for sale and ask who wanted to buy it (usually for outrageously high or low prices), dealing with a monster that needed to go to court, and stopping a dragon by sending it and the court monster onto a space ship.
It was pretty much what you'd expect from a nearly 6 year old's stream of consciousness. Oh, and a lot of it was dictated by the free to use minis on Roll20, as he would find one he liked, stick it on the map, and that thing was suddenly there.
He's looking forward to DMing again, and I'm glad to have him so excited about playing D&D!