The purpose of this study is to explore the effects of cooperative learning on cognitive outcomes in a public health graduate level Web-based distance education course. Specifically, the authors use a randomized control trial to determine the impact of two teaching pedagogies on learning effectiveness in three areas of the cognitive domain: (1) declarative knowledge; (2) procedural knowledge; and (3) higher cognition. This study examines various learner outcomes in distance education as influenced by cooperative learning. This study shows that cognitive learning outcomes are affected by cooperative learning when compared to self-study. While there was no difference in declarative knowledge and procedural knowledge, the cooperative learning pedagogy resulted in a 5% improvement in procedural knowledge and higher cognition capabilities compared to the self-study pedagogy. This research shows that cooperative learning experiences can be incorporated into distance education and results in advanced knowledge acquisition in the areas of public health inquiry, critical thinking, and problem solving when compared to self-study approaches. (Contains 4 tables.)