Don't give up. The some school systems are not the best. I had a very similar instance with my daughter around your child's age. My daughter she is now in the 3rd grade she struggles at time, but her confidence level is much higher now. The teachers she had took her little confidence down to nothing.
Long story short: The school was trying to force me to get her tested for ADHD. Needless to say she has it, but I held my ground received the additional help my daughter needed at the school. I also enlisted a friend who is also a teacher to help tutor her at home.
I understand your frustration. Honey, you have no idea how many tears these eyes has shed because of this. But, I was resistant I demanded that my daughter get the help that she needed. No child left behind. Quote the law use it. In addition, schools have funds budgeted to work with children on a one-on-one basis. Ask that your child receive an IAP Individual Accommodation Plan (IAP) to assist in your child's learning. This will help him as he goes through school.
My daughter no longer goes to the school that was causing us grief. But, you best beleived I made them work for their money. She now is attending a school where the teachers are taking the time out to work with students.
Talk to the principle to request a meeting to be held with the School Psych,Guide Cons, teacher and who every else is involved with your child's education. (DO NOT MEET IF THE PRINCIPLE IS NOT IN ATTENDANCE)
Random unscheduled drop-ins in your son class room to observe (Report issues to principle)
Request that class work be sent home so that you can reinforce at home
Request a daily report to be email or written to you cc: the principle
Enlist help outside the school
And remember to fight, don't give up. You must make it clear that you are a involved parent. You are and will continue to be active in your child's education. And that you require that do the same, by providing your son with the required resources to make him successful in his education going forward. Ultimately, what I found is that the teachers were lazy and they didn't want to take the time out to help the children that were behind, because they had other students that were progressive and understood what was being taught. If needed report the issues to the school board.
Hope this helps. Shoot me an email if you need some additional guidance or information.
You are on track, be persistent. You are not too late, you are right on time.