What special things did you do as a family when your college kid was in HS? Do that.
We visit the Christkindl market in our city, make sure to see a movie, and hit some favorite restaurants. My daughter loves bird-watching, so we often go on a few birding hikes, though not necessarily all of us on every hike if we don’t have time. If there’s a special exhibit at one of our city’s museums, we might go see that, too. We usually pick one night to go to one of the holiday lights displays (at the zoo or botanical garden – check to see if your city has something like this).
Winter break is not as long as you think it is, and your kid might want to spend a lot of time with friends, too. And there will be more breaks - no need to pack everything in now.