Explore the basics of combustion in this NOVA-created interactive resource appropriate for grades 8-12. It contains a set of simulations that promote understanding of how fire ignites and how chemical reactions rearrange the molecules of burning material. In the first simulation, users drag atoms to initiate hydrogen gas combustion. In the second simulation, students "break apart" a methane molecule, then drag individual atoms to form three new molecules: two water and one carbon dioxide. Don't miss the related links on the anatomy of a firework and an interactive temperature scale ranging from absolute zero to the theoretical "highest possible temperature".