This is a very fun project and also illustrates the strength of solar power. First we took a pizza box and cut around three sides of the top with a craft knife. Then we taped aluminum foil to the bottom of the flap. We lined the bottom of the box with another piece of foil, and then placed black construction paper on that. We then taped plastic storage bags that I had cut open. (You are supposed to use plastic wrap, but we were out and I had to improvise.). We then loaded it with graham crackers topped with chocolate squares and marshmallows. We placed it outside in a sunny spot, adjusting the lid so that it was at an angle that reflected the most sunlight into the box. As you can see from the glare, there is a lot of solar energy being collected. We checked back in about an hour and the chocolate was very melted, and the marshmallows, although warm, were not as soft as I would like it. If we do this again in the future, I think I will use mini marshmallows, however our taste testers approved of it just as it was!