NyBow good job on taking your son out. I've been taking mine out with me since age 3. I even started mine on those little plastic bow jobbers with suction cupped arrows. Then I moved them up to Bear wheeled fiberglas bows. Now my oldest is 15, and he's been my main hunting partner this yr. He's in love with hunting.
I know what your going through trying to keep your son interested, and patient. I gave mine grunt calls, can bleats, dressed them up like daddy in full camo. I'd point out different things in the woods. Sometimes all it took was a chipmunk or red squirrel to keep them interested. We saw deer or turkeys only a few times, but those times were enough. Kids are figgity, and tough to keep quiet. But hang in there, you'll find its more than worth it down the road. You'll have a fine hunting partner in yrs to come, and you'll look more forward to your boy getting a deer, than yourself.