Age-old problem I know. No family near so won't be visiting. We've done London museums and kids hate being dragged to National Trust type places. DH doesn't like going out to do active things (no walks, cycle etc, especially in the cold, and while I quite like a walk, kids will moan). I have suggested theatre, panto or suchlike, but it's really expensive where we are and no one seemed keen anyway.
I just want to plan a few things so it's not same old boredom complaints every day (or they all end up staring at screens, which we already do too much of).
What are you doing with kids to stave off boredom over Christmas?