Abby are you doing meds with him? I would seriously consider it if not. If you are and things aren't changing, and you should see immediate changes, this stuff isn't like antidepressants, where it has to build the effect is pretty much seen within an hour or two, he needs to try something different.
There are several books about ADHD and treatment, and in two different ones I read they indicate if you have only tried one med, you are probably not treating your child as best as you can, in other words, we all react differently to meds, and it's ok to try several to find which has the least side effects, and the most benefit.
I can remember crying and struggling to get my homework done, back in my day there were no extended release meds, and my mom refused to give an afternoon does, so by the time I got home I was bonkers, Not a good way to learn multiplication times tables, and so forth....
Please do yourself and him a favor and get him into a typing class in summer school, or get him a program to learn how. This was a lifesaver for my son. His handwriting is still nearly illegible, and his brain goes way faster than his hand can. Typing he can keep up, and he does all major writing assignments, and projects on the computer since he was in first grade. He learned typing by a computer program we had in KG that was a game, to help them learn basic skills and our district had a summer school program that offered a basics to computers class where he learned to type proficiently.
These kids like mine, and like I was, don't have a ton of friends, and are usually not part of the cool kid crowd, but I can tell you the friends they make are great ones, and they stick together through thick and thin, and stay friends for life.