Things do change once nobody believes in Father Christmas but we have adapted things. DC here aged 10 to 20.
Cinema trip
Ice skating
Winter walk to collect greenery and making garlands for stairs and mantelpiece
Buck's Fizz after breakfast when we are prepping dinner, ranging from mostly juice to rather stronger
Family secret Santa. On December 1st, when the Advent calendar goes up, we do a lucky dip and everyone gets an envelope with a name and £10 in. They choose, buy and wrap present and put it on person's chair before Christmas ddinner. It's nice to have a present at lunchtime and the kids loved trying to guess who their mystery buyer was.
Silly/funny crackers/after dinner game. Moustache crackers were a hit and Name that tune game with kazoos.
One of the surprise hits is a puzzle which arrives Christmas Eve in a goodie bag. The puzzle goes on kitchen table and gets done over the Christmas break with everyone helping out at different times. Mary Berry does this in her kitchen so that makes me feel like Queen of my kitchen 
Christmas Eve goodies, really only stuff I would buy anyway but it just spreads things out a bit (in a home bargains Christmas pudding bin bag last year):
new pjs
Hot Chocolate stirrers from Lidl
Christmas pasta from Lakeland
Lindor chocs
DVD
Family puzzle
Christmas books
White Stuff Winter candle