You may consider a couple of points:
1. reducing the challenge level of his academics may encourage him to coast even more, which may have the unintended effect of diminishing his development/implementation of study skills further.
2. middle school is a key developmental period for learning how to navigate increasingly complex social situations, and for beginning to work toward a balance of tasks (school, in this case) and relationships that is personally satisfying, and in alignment with one's own values. Work-life balance, in other words.
3. it may be that his personal goals are not what you think they are, or that he is still working through the line from present choices to future goals. Some additional patient, open-ended listening to his thoughts may help clarify this point.
