Welcome to the site :cool:
I see where you have gone to your User CP and updated information relating to your location. Grab a spot on the couch and tell us a bit about yourself. How long you have been riding, what kind of riding you prefer, where you are located, etc. We will do our best to hook you up with some fellow dirt bike enthusiasts.
We have a fair soze group in NorCal although they have not organized like the SoCal folks. Put up a post in the
SoCal Wrecking Crew forum. I'm betting they can steer you to some good places to take your son.
Again, welcome to the site, and shout if you have any questions!