This article presents one way to approach the case study versus theoretically driven approach to teaching comparative courses. The goal is to actively engage students in doing international studies, not simply reading about the work of others. The method derives a broad set of case studies from some theoretical approach. Students then conduct and present their own case studies. Students then use their own case studies and those examined by the class as a whole as vehicles for interrogating, critiquing, and extending that theoretical approach. These final exercises in theory-building are a significant part of this approach. The specific example presented here uses world-systems analysis as the vehicle for organizing comparative study of frontiers. However, this method could readily employ other theoretical models to examine other theoretical and/or empirical puzzles via specific case studies.