I have two boys 12 and 9, and I try to incorporate some exercise into our days. I map out routes for us to walk or run. I run, without the boys for exercise and mental therapy! However, during school time I include the boys. A walk would be at least 3 miles for us. I can usually get them to go longer if I include a game or good discussion.
Sometimes we play the alphabet game. Someone starts with A and that person needs to look for something along our walk that start with A. For example, acorn. Next person, B, bark. Next C, cat. Not only do the boys get exercise, but we also exercise their brains. Work on the observation skills and creativity. Some letters we will get creative with if we have trouble finding a noun.
I also will play math games as we walk. They boys have fun and before we know it we have went a few miles.
I map out the routes before and measure with the car so that they know and learn distances.
I also do a mile run with them. I start with a walk/run and then keep coaxing them to do more running. We keep time and they look forward to beating their last time.
I also show them how to properly warm up and cool down. This naturally leads to other discussion on the body and how to take care of yourself.
If you make it fun, it will turn into a healthy habit. Plus I see the added benefit of exercise and mental alertness. It all interconnets.
I hope this helps,
Susie