I have too few reputation points to add a comment to Robin's excellent reply, so I'm replying as an answer instead. Hopefully this will work, and please forgive me if this is out of the norm.
That being said, I wanted to add that "laziness" can also be a symptom of Inattentive ADHD. Inattentive ADHD doesn't necessarily manifest itself as the hyperactivity that's normally associated with the term "ADHD". The Inattentive type of ADHD is what used to be called ADD, and can manifest as forgetfulness, distractibility, or disengagement ("laziness").
You say your son is "entirely capable of getting A's and B's and where he not lazy would be quite capable of the other requirements... and he claims to want to do it, but is very lazy". This was me all through middle school, high school, and a lot of my adulthood. I wanted do things, but the distractibility and "laziness" often kept me from them. It wasn't until my mid-40s when I finally got diagnosed, started medication, and I could finally start using my brain like a "normal" person.
A lot of people think that if you have ADHD, then it's an all or nothing thing in terms of focus and distractibility. They say things like, "Well, if he can focus so well on a video game, then he can't have ADHD", or "he's not always distracted, so he can't have ADHD", but that's simply not true. People with Inattentive ADHD can focus, and can even hyperfocus to the exclusion of just about anything else, if the conditions are right. ADHD is what's called an "executive dysfunction", which means that it's a brain-based impairment that impacts a person’s ability to analyze, organize, decide, and execute things on time. It causes assignments to be lost, deadlines to be missed, and projects to overwhelm.
As a parent, I know that having someone say stuff like this is like they're coming at you saying that something is wrong with your child. It can be easy to recoil with an immediate thought of "No way!" and dismiss it immediately. I totally get it! But as an adult with ADHD, if someone would have pointed this out to me or my family back when I was a kid, SO much could have been different and BETTER for me as I grew up. I've had to make the discovery and advocate for myself all on my own. Having my parents help years ago would have saved so much headache.
That being said, just take a look at the two articles I linked above. If you think they describe your son at all, talk to him! Tell him some of the points you found or have him read the articles and see how he feels. Does it resonate with him? If not, then I may be completely off base, and there are no worries!
But if it does resonate, and if you want to dive deeper, find a copy of the book Driven To Distraction by Edward M. Hallowell and John J. Ratey. It was their later book "Delivered From Distraction", which is more about adult ADHD, that helped me find my way.
I hope that you don't take any of this as an attack or finger pointing or anything like that. I'm just speaking purely from experience and wanted to offer a point of view that I hadn't seen mentioned yet juuuuuust in case it could be helpful. Good luck! :-)