By following a paleo eating outline, I don't have to even look for gluten. No processed foods which are the worst source of hidden glutens, and watch closely, if he gets fast food as a treat now and then, many of them have wheat or other kinds of starch coating their frozen fries, or used pressed-formed potato mush product. McDonalds and In-N-Out were the only chains we would trust for Kiddo's fries. (She doesn't get 'em now, too carby which turns into sugars and sends her into weirdness.)
Figure out which treats *must* be part of the child's life, then figure out what to replace them with. Gluten free breads are either badly refined and highly processed, or expensive, or both.
I make a knock-out pan of scones, but it uses our home-made coconut flour (defatted dehydrated shredded coconut, what's left after we make coconut milk, after it's all dried out I run it through the food processor to grind it further.)
1/2 cup lard (you could probably use butter.)
2 cups coconut flour
2 or 3 eggs
1/2 tsp baking soda
water, stock, juice, or any other liquid of your choice depending on the other ingredients
Salt to taste
Savory seasonings if this is a savory treat, sweet spices if you're using fruit, all to taste
Seperate the eggs. Beat the whites to soft peaks, set aside. Rub the fat into the coconut flour (lumpy is ok) then add the rest of your dry ingredients. Add the egg yolks, and enough of your liquid (1/2 cup or more) to make it a slightly-less-than-stiff paste.
Get a 9 inch skillet, grease it up good, get it hot and sizzling. Fold the whites into the yolky flour mixture, fold in whatever other ingredients (cooked sausage crumbles, diced bacon, chopped fruit, shredded cheese, whatever you want) and scrape into the hot skillet, spread as evenly as you can (it'll probably be lumpy) and allow to cook on the stove only until the edges start to brown.
Pop into a toaster oven, convection oven, or regular oven at 375*F. Bake about 20 to 30 minutes until browned on top and firm in the center. If you greased the pan enough, it should flip out onto your cutting board. Let it cool a couple minutes, or as long as you can bear to wait, then cut into quarters and serve.
Oh the kids love it.
You might be able to do this with almond flour too, or a mix of the two - but I wouldn't go with any grain or bean flours on this, it's specifically for an ingredient that isn't starchy or absorptive. I couldn't guarantee it wouldn't be anything but a heavy, doughy frisbee in that case.