Mine aren’t teens yet so these ideas might still be too naff 
... and I have it in my head that you’re based in Ireland. If I’ve got my wires crossed you’ll have to ignore the local suggestions 
Foraging walk for pine cones, larch cones, holly, etc. Perhaps choose a spot that would be a good hike or bike ride and do the foraging as an add-on
Grow hyacinths or paperwhites or try forcing a poinsettia to bloom
Make candles (different ways to do this - simplest is roll up beeswax sheets that smell gorgeous, or get a kit in Art n Hobby, or go whole hog with dedicated double burners etc)
Etching or painting glass as lanterns or candle holders (upgrade from colouring in a crib scene!)
Making fondant figures to decorate Christmas cake, or do a whole scene. If you get a cake board (the thin one, not the 1cm thick one, you can make a top for the Christmas cake and just pipe on a bit of icing to hide the join. Fondant is just play doh for grownups!
Take a drive up over the city to look at the lights, or take a walk to photograph some of the houses that are lit up.
Diy Christmas crackers (sort of an upgrade on thinking up a joke for dad )-
Cheesiest Christmas song competition- play a song and the winner is the family member who can bear it the longest without switching it off.
Baking Christmas cookies (especially the stained glass Mary Berry ones). Gingerbread men from scratch. Or if you want to work off a lot of energy any variation of a sweet bread will take lots (and lots) of kneading.
Make seed balls for birds or use cookie cutters to make edible outdoor decorations for a tree
Orange pomanders with cloves (use a flower nail to punch holes in the oranges)
Can she do anything to add magic for younger dcs?
Keep a stash of Christmas themed books and movies that only come out for December
I think RNLI organize a Reindeer Run (5k) in Marlay Park in November
And it might be a bit too ambitious yet but I think there’s a walk that follows Red Hugh’s escape from Dublin castle up the Wicklow mts. It’s not one for amateurs, especially in bad weather, but perhaps one she could aim to do in a couple of years?
There’s usually a performance of Handel’s Messiah (or a few) if she’s appreciate something like that. The concert hall is worth watching for events at Christmas.
One year I painted a (back) window in a chrissmassy scene with poster paints. I’m thinking of doing something like a stained glass design some day which will never really happen we also cut out snowflakes for the kitchen windows. With a bit of Pinterest inspiration a teen could make a really nice display.
No idea if any of that is vaguely helpful. Dreading the teenage years!!