Our research explores multi-user virtual environments for teaching university-level courses. This paper focuses on undergraduate students’ reactions to five virtual worlds explored as part of a Computers and Ethics course. Written reports from twenty-five students were qualitatively analyzed with respect to perceived ease of use, user satisfaction, and user concerns. Our preliminary findings indicate that students’ perceptions and attitudes were mixed. Some students perceived virtual worlds as relatively easy to use regarding object interactions, communication and user interaction. However, there were some instances of difficulty in navigation and in completing some tutorials. Furthermore, students expressed concerns beyond usability issues, such as user misbehavior and cheating. These issues could become significant barriers to using virtual worlds for college courses. We present suggestions for reducing such barriers.