Since the beginning of the year our family began using cloth grocery bags, I bring them to the supermarket, to Walmart and even to the local farmer's market. One thing I can say about them is that they are quite sturdy, so you can fill them up twice as much. Best of all, it works for us and our environment.
Ever wonder where all those plastic shopping bags go? This is a great slide show to share with the children, after all, they will be the most environmentally aware generation.
http://www.poconorecord.com/apps/pbcs.dll/article?AID=/20080506/MULTIMEDIA02/80505016