Making your own yogurt is so easy. Really worth the small amount of time and effort. And if you prefer "greek" yogurt, just strain it after you make it. Yum.
Heat the milk in a pan until scalded (not quite boiling but almost), stirring to keep it from scorching on the bottom. Cool the milk back down to lukewarm. Add a bit of yogurtstarter - a tsp of the yogurt you've got now would work. Whisk it through nicely. Pour the milk into clean containers and keep warm for 8-12 hours (the proof setting on an electric oven, or the pilot light in a gas oven, are enough). Some people use a thermos, others use a cooler to keep things warm.
We found that environmental factors were huge with my son - he had pretty rabid ADD.
He wore shooting ear-muffs to do his schoolwork to shut out distractions. He was not allowed to watch more than one episode of anything animated per day (seriously, that had a HUGE effect), and he was not allowed to play computer games (again, massive effect).
These are both things that have been shown in studies to aggravate certain centers of the brain. In my son, it seemed to disconnect him from reality also. When we could keep him firmly grounded in reality, he did so much better.
Later, we had to watch for other things - one reason Harry Potter makes no appearance in any form in our home. He obsessed over it, could not get anything accomplished. Legos were that way for a while too.
Routine chores are helpful in teaching a kid to function. I'd put them at the top of the list. If you can teach them to do daily care tasks, and keep them doing them over and over until they can do them on "auto-pilot", then their mind can go wherever it wants, or if you can teach them to do it in spite of excess energy, then they can learn to discipline themselves to get the necessary things done.
My son still has raging ADD. He's now a successful supervisor in a survey call center, and is being trained for another promotion. He's writing a novel, and is a talented graphic designer, getting ready to attend college. His academic test scores are always near the top.
When he was on his mission, he ran into a family they were teaching who had a son with similar behaviors. He began telling the mom what I'd done to help him. He also told her that he remembered it seeming very hard - like he was being picked on. But that after a while, he realized how much it had helped. She wrote to me, and asked me for details and told me that when he had talked to her, he'd told her how much he appreciated that I'd been so strict about it, because he knew how much of a difference it had made in his life.
He's one of those kids that brings constant warmth to my heart because of the person he has become.