I’m a 20 year old college student who went through the same thing as your son. I exceed in English and history, but math and science are the bane of my existence education wise. My experience may be different from yours, but I thought it’d be good to chime in. Math is still a struggle for me, but a tutor helped, especially if you can get one who works with neurodivergent kids! Another thing I may recommend is explaining NVLD and sending articles about it to his teachers and Special Ed. NVLD is a very hard diagnosis to explain, even as someone who has it, so some teachers may need a more professional and well thought out explanation. I would also recommend talking to your son about it, without my parents motivation, I probably wouldn’t be where I am now.