ORIGINAL: jester_s1
Fast gratification is the key with youngsters. He probably doesn't care about perfectly round loops and greaser landings like you do. He just wants to fly.
Let him enjoy those and if he sticks with it for more than a month maybe let an instructor take him up on your trainer.
I agree with the former, but I would suggest getting him on at least one session with the instructor before going as far as the sim.
Normally that first session will "hook" anyone and motivate them to keep with it.
We've done this with 12-15 year olds in our club's summer camps, and the motivation sticks with them this way versus starting with the sim alone.