At that age they seem to get bored when things are slow, but I have started a son and daughter and some grand kids. I always went for something that was a sure bite to start with to build their hunger, TR is loaded with Goggle eye, and all the perch family from this area. If he gets bored try changing the quarry. The second, and probably the most important, when they get bored don't push them. Let them look at the water, fiddle their thumbs or what ever makes them happy. They may get bored with that and start fishing again, this is what usually happens, but if not that should be fine also. Patience, build only happy.