The Mitten Thaw. Sipping hot cocoa without getting burned, first one who does (or fakes it awfully well) wins! There should be award for best hat head, as well as for who can put on the most layers.
Toboggan runs... heck, let's go with all outdoor downhill equipment commonly found in a garage, including sleds, discs, cardboard boxes, whatever.
Ice skating with little kids! That, my friend, is a true test of coordination and balance.