making Christmas tree decoration (you could make this several activities by specifying an angel, a bauble, a reindeer, etc)
Looking through their toys to find old, but nice ones, to take to the salvation army
Taking said toys to the salvation army (or local hospice, etc)
making truffles as gifts for the neighbours
learning a Christmas song
writing letters to Santa
making a gift (drawing or handprints) for Daddy
making a gift for Granny, etc etc
Paint/colour in a (preprinted) christmas tree picture then glue cotton balls on for snow.
Paint/colour in a rudolf picture then glue a big round red thing on for his nose.
Collect pine cones then paint/glitter
Paint mdf shapes, then glue on gemstones/glitter (tie a ribbon through or add a photo on one side & it becomes a nice christmas gift for family)
Trip to the library to find some christmas story books
you could make Christmas related stain glass window decorations. (Cut a christmas shape into the centre of a piece of cardboard/paper then put cellophane in the middle and hang on window)
You could make "Christmas" Lanterns (fold a piece of paper in half. Cut almost to the fold all the way along the paper. Open, fold the other way, secure, then hang from ceiling).
Print off some Christmas colouring pages and colour in
Make Christmas Cards for relatives
Make food for the reindeer (oats with some glitter in it)
Bookmarks