Mine are 21 and 23, now. I really miss the early days around Christmas time. (Yes, we say Merry Christmas) I use to go to great lengths to make the kids Christmas fun. I would knock logs out of the fireplace and track ashes around the carpet with boots. (My wife LOVED that

) Hide big gifts in the trunk of the car, and send the kids on a treasure hunt to find it. (after they out grew Santa) I would wrap up a message in a box, that tells them to look under the floor mat, then there would be another note there telling them to look in the dryer, then look here, then there, then after looking all over the house (and outside the house), they were happy with what ever it was, just to get back inside where it's warm and dry. THAT was FUN!
My 21 yr. daughter coaches Crew (U.S. Rowing) and is going to have the kids row an 8 man shell (with a Coxswain in front with a red nose) All the kids will have antlers on and will be towing a boat, called a launch, that I have just been "nominated" to convert to a Santa Sleigh with Santa in it. Fun time of year.
Enjoy your kids. They do grow up FAST!