Just an idea, but maybe you should look into scouts for your son. I was a scoutmaster for 12 years and saw plenty of boys with ADHD. They mostly did well. First of all, the outdoors is a great place to burn energy. Second, there are scouts that are very accepting of others with challenges. Not all, but it’s a good environment. Given that your son is in 4th grade now is a great time to join. He’s the right age to join cub scouts, make some friends and learn the basics. In about a year he’d join a boy scout troop and do a lot more outdoor activities. Different packs and troops have different personalities, so ask around. If you like the outdoors then you can also participate.