These jello-flavored cookies are great for holidays, because the recipe makes about a billion cookies, and you can change the kind of jello you use depending on the color you want. I suggest Lime and Cran-Raspberry. We used strawberry jello and dipped them in dark chocolate when we made them for Valentine's Day last year, and they were delicious.
I came across this recipe for peppermint cupcakes the other day and decided to try it, and they came out so pretty!
And lest we forget, you could always tackle a gingerbread architectural feat. There are lots of patterns at this site.