A technology-mediated solution to enhance the learning experience for students in a large lecture setting was evaluated. Online problem sets were developed to engage students in the content of a human biology course and implemented in the classes of eight faculty coordinators. The weekly problem sets contained several multiple choice problems, each with space for an open-ended rationale. Each quarter, the online problems were worth between 5% and 15% of the student's grade. The evaluation drew on multiple sources of data including a student survey and focus groups. Overall, approximately 90% of the students reported liking that the problem sets were presented online. Between 70% and 79% of the students reported working with a partner or in small groups while completing their problem sets. Data supported that the students were actively involved with the material and that they generally thought about the problems deeply and critically. Involvement with the problem set varied from faculty member to faculty member, and only one faculty member interacted fully with the system and maintained regular student e-mail feedback. Course assistants were instrumental in reviewing student performance, and they carried much of the responsibility for writing and uploading the questions. Future studies should look more systematically at the student benefits of such a system. (Contains 29 references.) (SLD)