In a 2009 article published in Science (2009:323) Smith et al., found that when undergraduate students at the University of Colorado-Boulder were posed with a multiple-choice question during lecture, and then were given an opportunity to actively engaged in small-group peer discussion regarding their individual responses, they increased their conceptual understanding of the course material, and were more likely to answer a similar multiple-choice question correctly. Furthermore, the improvements in learning occurred even if none of the learners in the discussion group actually knew the correct answer to the initial question! So, why does peer discussion work? The authors speculate that, “…justifying an explanation to a fellow student and skeptically examining the explanation of a peer provide valuable opportunities for a student to develop the communicative and metacognitive skills that are crucial components of disciplinary expertise” (pg. 124). This study provides further support for the use of peer discussion as a simple and effective teaching strategy to encourage active learning in the university classroom.