The Jewish Coalition for Service is sponsoring a service trip to Israel to help with rebuilding the areas most hit by the recent war. It’s for folks aged 22-35, it’s December 25-January 5 (but they seem to indicate that you could stay on in Israel longer than that), and the cost is subsidized, so participants pay only $180 to cover airfare, food, lodging, etc. Check their website for more information and deets.