Abstract. We describe the design of the Invention Coach, an intelligent, exploratory learning environment (ELE) to support Invention, an exploratory learning activity. Our design is based on a two-pronged approach. Our own study of naturalistic teacher guidance for paper-based Invention uncovered phases in the Invention process. Prior research on the mechanisms of learning with Invention activities revealed specific instructional strategies. These two sources informed the design of the guidance offered by the Invention Coach. To our knowledge, this is the first design of a guided environment for Invention activities inspired by a model of naturalistic teacher guidance. Our work offers insight into styles of guidance that could apply to other exploratory learning environments.