There was an interesting article in the Sunday, March 1 issue of Parade on solar cookers. As the article says, "Take two pieces of cardboard, add some tinfoil and sunlight..." Solar cookers are helping women in Africa because not only does it save fuel, women refugees don't have to leave their camps to look for firewood. They're safer in camp, and they can make money by assembling the cookers in workshops.
I've also read about solar cookers in articles about camping and living off the grid. This would be a good craft to teach kids at summer camp and at home. And for those who'd like to help the refugees of Darfur and elsewhere, go to: