My situation is different because my H has no involvement in the day-to-day of the kids and sees and talks to them very little (except during touch and gos).
Is anyone addressing why your son is not doing well in school? Could it be that his parents are having marital problems and he feels like this is an area where he can exercise control or show you guys how hurt he is. I personally don't like the idea of grounding in this situation. Maybe he needs extra support. Is anyone sitting down with him while he does the work? Is he seeing a counselor? If not, maybe he should.
You can't go NC or dark with kids. You can go dim. Strictly business. Keep it to the kids, the house and the D when she brings it up. Don't kid yourself and use the kids as an excuse to contact her. I think I did this in the beginning. Mine could offer nothing during those times so I just stopped telling him entirely, even when it involves big things.
