To ensure active participation and student preparation, the authors designed four roles. Each student was assigned one of these roles (described below): gatherer, questioner, answerer, or historian. Students rotated among the roles approximately equally throughout the semester in a self-selected order. In each group, the gatherer chose the article and posted it to the course management software (moodle, Moodle Pty Ltd., Perth, Australia) by the established deadline of 3 days prior to the in-class discussion. The gatherer could choose any recent (less than 10 yrs old) article about any aspect of biomechanics from any peer-reviewed journal. Students were especially encouraged to choose articles on topics of personal interest or on their chosen topic for the literature review assignment. S/he also posted an 8–12 sentence summary of the article prior to the in-class discussion, in preparation to lead the discussion. Prior to the in-class discussion, the questioner posted at least two questions about the article to moodle; these could then be used as a starting point for the group's discussion. The answerer posted answers to these questions following the in-class discussion. For groups with four students, the historian investigated the authors of the article with a focus on their collaboration and publishing history and posted a summary of relevant information prior to the in-class discussion. Safeguards ensured that discussions could proceed if any student failed to do their part. If the gatherer failed to post the article by the deadline, the teaching assistant assigned an article to the group. If the questioner failed to post questions, the group was tasked with identifying both questions and answers during their in-class discussion. Posts to moodle were accessible to all students in the course. In keeping with good assessment practices in cooperative learning , this formal preparation structure permitted individual assessment (described below) and fostered a starting point for the in-class discussions.