Southeastdad - good points and I considered that possibility in my reply. Post-high school colleges allow kids with issues such as these to compete. They'll provide additional testing time and tutoring to help him among other options. B's and C's are outstanding if that is the best that he can do and I wish I wouldn't have implied otherwise.
It sounds like he is a max effort kid and that is to be commended/encouraged. My reason for posting was that if he is rejected initially by a four year school because of high school grades, he can still achieve his goals by going the JUCO route first, getting suitable grades, and completing his four year degree thereafter. I could have worded things better, but it sounds like your son has already gotten the message of effort. I still don't see any reason why he can't continue on his educational path - he'll just have to work harder than other kids. Fortunately and proudly for you, he already knows how to do that. All the best to the young man. Feel free to send a private message if I can help him in any way.