Cub Scouts can only shoot BB guns and Archery at Council events. Boy Scouts (11 years) can shoot bolt action 22's. Unless the troop has a range safety office and a rifle instructor they'll most likely shoot at summer camp or other council events. Best to find a Troop that is into shooting sports.
I know I am late to the game but try Dustin Ellermann Marksmanship camp which he holds like three or four times a year on weekends. My daughter went to his camp four years ago and had so much fun. His camp is locaterd in Zavalla, TX