Truth is, he spends far too much time inside, so this is good for him. He really doesn't need to spend more time with the Pokemon cards or watching TV shows. Okay, he's discovered Star Trek, the original series, so that's not as bad nowadays as it used to be when it was nothing but Disney Channel reruns, but still, he really needs to get out.
One of the fun things he discovered is that from horseback, you can reach the plums and apples from wild fruit trees on the side of the road or trail, even when all the lower ones have all been cleared out by walkers-by.