<p>I don’t think that bogibogi’s son needs to be nagged to do the work. He gets Bs, after all. What bogibogi seems to feel is that he is not putting forth the effort to get As in all subjects because some do not interest him.
It may be due to lack of maturity, either through not seeing how lack of effort might affect his chances down the line or through lack of understanding of literature and history; or it could be because those subjects are not taught in a captivating way.
If he could be brought to think that with only a little more effort on his part, his grades would improve dramatically, then it is worth letting him know it and reminding him. However, I do not think nagging will be very productive.</p>