The circles and patterns in a tree's stem tell a story, but that story can be a mystery. Interpreting the story of tree rings provides a way to heighten the natural curiosity of students and help them gain insight into the interaction of elements in the environment. It also represents a wonderful opportunity to incorporate the nature of science. In this activity, appropriate for grades 3-6, students make connections with the work of a scientist as they solve a mini-mystery using tree-ring evidence. (Contains 2 figures and 2 online resources.)