I think events like the Katrina disaster are awonderfully opportunity to teach kids values in a number of areas:
http://seattlepi.nwsource.com/local/...inakids08.html
Not only can the learn to help others in need, they have the opportunity to learn about money and how to earn it. It's especially powerful if it is initiated by the kids themselves. if your kids express interest in helping, take the time to work with them. It will pay off in countless ways.