The goal of this project was to help science teachers shift to a more inquiry-based teaching style by supplying learning tools that support a more student-centered approach. The project employed PSI (Personal Study Instrument) Sim Modules, a simulation-based electronic learning environment designed to address misconceptions in middle school science. Our findings indicate that using such tools will encourage teachers to engage in critical reflection about pedagogical content knowledge which can have a transformative effect on their teaching. (Contains 5 figures and 1 table.)