want him to do well and excel at school.
However, are you putting a strong emphasis on his achievements and strong points? I mean, he sounds like he is succeeding and there is so much focus on becoming better or improvement that it can make a person feel like nothing they are doing will ever be enough.
So, the struggling with a particular subject is stressful enough, but it might be a good idea to make a feedback sandwich for him by pointing out how well he has and is doing and how you understand that not everyone excels at all subjects, as a matter of fact.
Strong emotional support and sound feedback will at least shore him up and might relieve the tension of not feeling "good enough" with a "low B". Then, from there, maybe you can also help him find more motivation and enthusiasm, as well as a healthy ability to BE rather than just be in a process of becoming.
You might also want to look into his proclivities for learning. It is not always a "one size fits all" activity. I would suggest looking into how he is being taught algebra and see if there are other ways to help him approach it. He is dealing with higher levels of abstraction and not everyone comes to a point where they can deal with it well at the same age. The Internet is your friend in this case.
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