As our closest celestial neighbor, the Moon is a familiar and inspiring object to investigate using a small telescope, binoculars, or even photographs or one of the many high quality maps available online. The wondrously varied surface of the Moon--filled with craters, mountains, volcanic flows, scarps, and rilles--makes the Moon an excellent context for students to explore the methods scientists use to date geologic features, while learning about scientific observation and inference. This activity includes a unique application of the law of superposition that allows students to explore the relative ages of key lunar features and their origins.