@cak Personally, I think he’ll end up okay, if not great later on. Just provide him with love and support and as long as he has a few good friends, he should be great.
I was in a similar boat as your son. I was the outcast at school, I was thought to be peculiar and a nerd for being able to read and do math faster than all the other kids, and I was also a slow runner which left me left out in many activities on the playground. I wasn’t welcome to games of tag, kickball, and several other games. And was actually beaten up several times for being a “weirdo.”
Fortunately I did have a few friends that were very close, and that helped, I learned – as I hope your son does – that even one loyal and trustworthy friend is worth more than a multitude of friends who are simply your friend because you are not different or have something that interests them.
By the time high school rolled around, I had developed quite a few friends, and participated in sports such as swimming, wrestling, and water polo (things that don’t require running all that much) and was more or less proficient in all three sports. Kids actually respected me more since I was able to do well in academics and athletics unlike their kindergarten-5th grade counter parts who called me a freak for doing better than them at academics, and a wuss for not being able to run fast.
Today, I’m a cadet at West Point, and I would guess that most people would say that I turned out well, and I thank having a few amazing friends for not making me become a bitter introvert who hates everything (I just ended up being a nihilist, but I have had views leaning that way since day one so that’s more attributed to genetics I guess than anything).
So if your son has a few good friends, and supportive parents (the latter I lacked quite a bit of), I’m sure he will be able to shine brilliantly and eventually, he’ll get the proper respect he deserves from his peers.
PS: If you could get him into a GATE or TAG program (or something of the like) that may help him to be around others who are similar to him who are also probably very willing to be friends and provide healthy and friendly competition.
Perhaps this has made you feel a bit better or not too worried about your son, and if it doesn’t seem all too coherent, I apologize, I’m in the process of crashing from a sugar fueled adrenaline rush from earlier today.