Computer simulations, such as the BioQUEST Environmental Decision Making (EDM) program, represent a viable supplement or alternative to traditional science teaching approaches. This study concentrated on the manner in which knowledge is acquired and then disseminated through the use of the simulations. In addition, the study took into account the nature of science by revealing what notions of ecosystems and simulation were revealed when students encountered concepts imparted to them via this method. The following research questions guided this study: 1. What content knowledge do students use to solve ecology problems? 2. What procedural knowledge do students use to solve ecology problems?