In this study we describe the use of clickers in a second year data structures and algorithms module. In recent years instructors in higher education have begun introducing classroom technology that allows students to respond to questions during lectures. Studies have shown considerable benefits in terms of attendance, classroom engagement and allowing instructors to gain instant feedback (Caldwell, 2007; Kay & LeSage, 2009). In this study students were assigned to self-selected groups of three. 20% of the final module grade was earned by answering questions during lectures in competition with other teams. We found that the use of clickers had a dramatic effect on both attendance and engagement in the class. Students were far more likely to ask questions and defend their points of view, both before and after lectures. At the end of the semester the majority of students rated the clickers positively. However, the final module grade was lower than previous years. An anonymous survey suggested that although students enjoyed working in groups, they were less likely to take personal responsibility for their own learning when there were others on the team that could do the work. In light of this, we recommend allowing students to discuss questions together during lectures, but awarding marks individually.