In this article, the authors present a new way of teaching the phases of the Moon. Through the introduction of a self shadow (an idea of a shadow that is not well-known), they illuminate students’ understanding of the phases of the Moon and help them understand the distinction between the shadows that cause eclipses and the shadows that relate to the phases of the Moon. Then, they follow with two easy-to-do demonstrations that help students further develop their understanding of the reasons behind the patterns of lightness and darkness in the Moon’s phases.