I've got a friend with an 8 year old son who is fascinated with motorcycles, and dirt bikes in particular. My friend was recently asking me how to she could get her son an introduction to riding, taking some classes or an instruction course. They don't own bikes and she doesn't ride, but I'm sure she'd get one for him if he takes to it. I'd take him out but the smallest bike I have is a CRF230.
One idea I had was to contact Danny Walker at American Superbike since he's up in my area (Fort Collins). Do any of the local tracks offer intro days/classes/camps? Does anyone have any other suggestions?