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Clickers and Peer Instruction

Peer instruction using clickers has been popularized by Professor Eric Mazur at Harvard University and is a strategy which aims to help students develop productive ideas about the material they are studying by discussing conceptual questions with peers during class and answering multiple-choice questions about these concepts posed by instructor.

During class, the instructor briefly lectures (5-10 minutes) about a particular concept or idea. Then, he poses several conceptual questions regarding that concept in the form of multiple-choice question. For each question, students first answer it individually (via a classroom response system which could be an electronic clicker or a card with A, B, C, D or E to denote their choice for the multiple-choice question), then they discuss their answer with a peer, after which they answer it again.
The essential aspects of this method which help improve student learning are the following:
  • It is a great formative assessment tool which communicates the goals of the course to students in the form of concrete questions so that students have a good idea about the level of understanding that is desired pertaining to a particular topic.
  • The feedback that the instructor obtains from students’ responses can be used to adjust the instruction and focus on issues that most students find difficult. The feedback can also be helpful in tracking the progress of students individually and of the class as a whole.
  • The conceptual questions are designed to uncover a typical unproductive way in which many students reason about the concept (i.e., the alternative choices deal with common difficulties, a misconception or alternate conception).
    • These unproductive ways in which students reason about the material are often revealed by discipline-based research, or from experience teaching and listening to or reading students’ reasoning in homework or exams.
  • Being able to come up with plausible incorrect answers that students may select if they do not know the correct answer is important: the most effective clicker questions are the ones in which the level of difficulty is such that roughly half the class selects the correct answer, and the rest gravitates towards one or two incorrect answers.
    • The questions should NOT be too easy! (e.g., 80% of students answer correctly).
      • Students may be misled about the difficulty of questions they should expect on an exam.
    • Students overwhelmingly see challenging questions as most useful for their learning.
  • The peer interaction aspect (discussion between two or even three students sitting next to each other in class) is essential because:
    • Students have to articulate their ideas to their peers and the process of articulating their thoughts helps them solidify their ideas. Therefore, this method helps all students including those who may have to do explaining to their peers.
    • Peer discussions tend to lead to the correct answer most of the time (i.e., students with correct answers are more likely to convince students with incorrect answers than vice-versa; furthermore, two students with incorrect answers can discuss with each other and end up with the correct answer – in physics this has been shown to occur in roughly 1/3 of the cases, see this article).
    • Discussing several questions each class breaks the monotony of lecture. Students become intellectually engaged because they must discuss the material with their peers. They are more attentive during class and tend to value class time as an important learning experience. Most students also enjoy working with peers.
This method is highly versatile and can be incorporated in various instructional settings fairly easily (including large enrollment classes) without requiring significant changes (either in terms of instruction or class architecture).
Eric Mazur who popularized Peer Instruction is a very engaging speaker, you can watch him describing this method here, or, for a shorter version, watch him here.
Books on using the Peer Instruction method are available for:




Additional Resources
Free Clicker questions (referred to as ConcepTests, GoodQuestions etc.)







    • Computer Science

      • Peer Instruction for Computer Science
        • A comprehensive collection of peer instruction materials for
          • CS Principles with Alice
          • CS1 in MatLab, CS1 in Java, CS1 in Python
          • Computer Architecture
          • Theory of Computation
          • Programming Languages
          • Discrete Mathematics
          • Operating Systems
        • To access complete materials you just need to fill out a form with name, email, and organization/institution


    Articles on clicker question development, use and effectiveness of Peer Instruction/clickers