This paper describes a framework for studying and evaluating learning environments which contextualize school science content within a larger real-world scientific endeavor, such as carrying on a space mission. A central feature of this framework is its incorporation of recent research on content-specific personal interest. This framework was developed and tested in a pilot evaluation of the Challenger Learning Center's M.A.R.S. (Mission Assignment: Relief and Supply) learning activity. This activity consists of a series of classroom activities which prepare students for a simulated Mars