“What is life?” This deceptively simple question lies at the heart of biology. In this activity, students work in groups to come up with their own definition using a set of prompting cards that differs for each team. In doing so, students gain an appreciation of the complexities of addressing this question. The activity takes approximately 60–90 minutes to complete, but students often discuss its implications for weeks afterward. This activity successfully engaged freshman undergraduate students and could easily be adapted to high school and even elementary school students.