I would encourage you to be in close communication with you son's school. First, you may need to advocate for more of different services or accomodations for your son at school. If you don't feel that your son's school is supporting him to the extent that he is making progress and feeling successful, you should advocate for some changes. At the same time, I think it is great that you are making yourself part of the solution by working with your son at home. But, you shouldn't feel that your son's academic success relies solely or primarily on what you do at home. Also, your work with him at home is likely to be most helpful if it is matched to his school curriculum, so it would be best to use his school as a resource. If your son has not been formally diagnosed I would encourage you to have him evaluated so that he is eligible for the services that he needs.
I completely understand. My 12 yr old son was diagnosed 5 mths ago with Asperger's Syndrome. It had been suggested to me over the years to get him tested but I thought my son was fine and would grow out of his odd behaviors. It wasnt until last year when I went back to school to be a nurse that I really started to realize through my training that my son had an autistic spectrum disorder. The treatment that seems to work the best for Aspie kids usually envolves a behavior analyst. The best thing you can do for your soon is to have him get an actual diagnosis rather than just a self diagnosis. With a diagnosis it will open up doors for him to recieve additional services from schools and medical professionals such as special schools and more intense interventions. It is our job as parents to be our childs advocate. If you get your son a diagnosis the school will be required to pay for the services he needs to succeed in school.