The academic literature on teaching and learning provides compelling evidence that active and collaborative learning strategies, as well as frequent formative assessments with corrective feedback, significantly improve student learning outcomes. A central challenge faculty face in teaching large undergraduate courses (150 students) is providing students with these types of learning opportunities without overburdening the teaching staff (instructors and their graduate student teaching assistants). To address this challenge, this study assesses the use of PeerWise, an online pedagogical tool that allows students to write, share, answer, and discuss multiple choice questions (MCQs) in a large enrollment political science course. Using both quantitative and qualitative student data, it finds that student use of PeerWise is not only positively correlated with student learning gains at statistically significant levels (p = 0.001), but also that it promotes student perceptions of learning and motivation to learn.