There's loads of stuff as long as you keep an open mind that they are growing up with their own opinions, make sure you know in your own mind which are the actual important family traditions, and which bits can fall by the wayside. I've found that giving teens actual control over what events or bits they want to join in on has meant they're up for most things (I may have particularly amenable ones though!).
Mine are 15 and 16, hits are Christmas movie marathons (we include Christmas horror films as well as Home Alone and Muppets Christmas carol) in the run up. Typically highly contentious shortlisting of films, with an annual debate on whether die hard counts as a Christmas film.
Some sort of Christmas light trail is still a hit.
Christmas shopping trip, where we loudly exclaim how lovely something is if it's wanted under the tree.
We still do letters to Santa.
Still do board games, though more adult ones.
Still do a gingerbread house, but the kids organise it.
Weirdly - they really want matching family pajamas - I'm just going with it!