Oh have you touched on a subject near and dear to our hearts. We just drove half way across the country so my husband could participate in an orienteering meet. He's been orienteering for over 20 years. All of us have done it as a family and DS8 is getting close to being able to participate on his own. It's a great family activity and it's such a "geeky" crowd (in a good way! We fit right in). I highly recommend giving it a try. You need a compass and a whistle. I would start by letting him lead and you follow on an easy course. Courses are rated by color - white is the easiest, I believe.
Campfire is another option to scouts - I know their programs can start at kindergarten age. Both our kids will be participating in a new chapter soon.