You can’t do a lot if they are not inclined. You can do a few things:
- Encourage them to be in the highest level classes (honor, AP) that they can handle in the areas they are interested in. Don't push for a full load of those type of classes if they struggle or just have areas that aren't their best subjects. But do encourage some of those classes in their stronger areas.
- I took both of my kids on ONE college visit sophomore year. It was just to introduce them to the process we would be spending a lot more time on starting junior year. It also acted as incentive for both of them. Both schools were probably matches or low matches for them at the time of the visit. Both told me later that their takeaway was, "Nice... but I think I can do better if I work at it." It helped for them to see what they were working for -- an actual visit to a school where we could talk about the GPA and test scores needed to attend there, needed to earn scholarships there, and to look at various college majors.
- I would attach some privilege to decent grades. By decent, I mean trying to stay above a 3.0 at least. A student over a 3.0 will have college options. Maybe there is some privilege lost if they are below a 3.0, and something gained if they are over a 3.5. But then leave it to them. I wouldn't hound them or nag them about grades. I'd check in to see if they needed and were receptive to tutoring in anything they are struggling with (my kids were just awful at foreign languages -- that is the one subject we got them some tutoring in).
- Overall, love the kid on the couch. Don't let their HS years turn into a never ending struggle about grades or ECs. Offer incentives and disincentives, but don't make it a huge deal in your relationship with them.