We took advantage of the larger gathering to play a game of yut-nori, a game of chance and strategy using four rounded sticks as a sort of "dice." New Year's is really the only time when we play this game--among the older generation card cames such as "go-stop" are preferred, but the complicated rules have so far eluded me.
Our game pitted the Song family against the in-laws, and I'm proud to say that we men asserted ourselves strongly, winning in straight sets.
It's hard to find a good set of rules in English for this game, but the best by far is on Wikipedia, which can be found here. Check out the "special rules"--they can make the game more exciting, too. It's really a very simple game, and one I would highly recommend to families hosting Korean exchange students.
I forgot to take a picture of our family playing yut-nori together, so I borrowed this one from flickr (Credit to johl).