Why not go for something about art in general? You can hold an open painting exhibition (or collaborate with a place, doesn't have to be a gallery) from different artists regarding holidays, or you can make a competition for children (and adults) with Christmas theme quizzes and music puzzles and/or a lottery.
IMO, it will be relatively easy to find sponsors for the prizes, which do not have to be expensive. Specifically for the prizes, you can also collaborate with special-purpose organizations/ centers, such as rehabilitation centers, addiction treatment centers, etc from which some already make ornaments and other seasonal items and for sure have more moral weight than other similar items.