Before you throw an object into the air, it is wise to remember that “What goes up must come down.” Similarly, before you throw an object away, you should recall that “mass cannot be created or destroyed during a chemical or physical reaction.” In other words, just because you throw something away, it doesn’t mean it’s gone. NSTA and the U.S. Environmental Protection Agency have developed the Life Cycle of a Pencil to teach students about waste disposal and the environment. This resource is designed to help students understand the science behind the “life” of an ordinary consumer product—the pencil.