Fun winter craft: make snowmen by stamping white paint using different-sized disposable (paper or plastic) cups, then add decorations like buttons, googly eyes, pipe cleaners or real sticks for arms, paper scraps. Other fun craft ideas at this site.
Wad up newspapers for a snowball fight. Clean up by making snowmen with the "snowballs." Stuff white garbage bags and decorate with paper scraps and scarfs. (or cover beach balls with white garbage bags.