If you go to the natural treatments forum and the archives for that you'll find lots of info on gluten and casein free diets. As someone else suggested though, do try immediately taking him off of ALL food dyes. The Feingold or gluten, casein will take you a bit more time to totally clear from his diet. Right now read every label and if it says food dyes, don't let him have it. Tell school the same. You'll be amazed what this eliminates. Pure apple juice, grape juice, orange juice are fine. But check the label to be sure it's not good food coloring added.
In terms of the gluten and casein free diets, many labels for the glutens in particular say gluten free. There are many websites with recipes and even prepared foods that you can buy. It's not anywhere as hard as it seems any more.
