Looking for a way to engage your students in writing equations to model angle relationships? Then this low-prep, differentiated, self-checking activity, “MISSING,” is for you! In this activity images appear and then disappear after students correctly write and solve an equation to model an angle relationship. Each time the image disappears an icon in the original picture will mysteriously go “missing.” When the image reappears, students are prompted to guess the icon that has gone “missing.” As