This poster reports on the preliminary results of a study comparing the effectiveness of system dynamics with traditional, lecture based, methods of learning about wetland ecosystems. The study tests the hypothesis that students utilizing a system dynamics approach learn more and retain more of the material presented to them than with the traditional teacher-based approach. Students from the Las Vegas school district participate in one of two treatments, as the experimental or the control group. Students in the experimental group are presented with a lesson utilizing four system dynamics models about the Wetlands Park Nature Preserve (WPNP) in Las Vegas, Nevada. Students are given a pretest, prior to instruction, and a posttest two weeks after instruction. To assess student learning, understanding, and retention, scores on the pre and posttest are analyzed.