Peer Instruction (PI) is an evidence-based, student-centered pedagogy originally introduced in 1991 by Eric Mazur in his physics classroom at Harvard University . It’s a highly engaging, active learning strategy that encourages students to create knowledge among themselves.
Peer Instruction generally involves the following steps:
The instructor poses a conceptual question; this is also called a “Concept Test” to probe students’ understanding on a topic just covered by lecture or pre-class reading.
The instructor gives students one to two minutes to think, and then asks them to record their individual responses. These can be collected or not, at this point, either on paper or via a technology tool like Google or iClicker Cloud.
The instructor asks the students to discuss the reasoning behind their responses with their neighbors and to explore any differences in their answers; this peer discussion can last for two to ten minutes, and the instructor may find it useful to move around the room listening to the student discussion.
Once discussion is completed, the instructor repeats the question and collects the new responses.
Finally, the instructor provides immediate feedback on the results, and explains the correct answers or asks volunteers to clarify any remaining confusion &.
Unlike more free-form class discussion activities, in which, often, only a few students participate, Peer Instruction involves every student in the class. It gives quiet students the opportunity to be more engaged through their active participation in the questions/polls and in the peer discussion . It has been found that PI works best when implemented with a “flipped” classroom approach and when students are graded on their participation in the activity rather than on answering questions correctly 
Used in this way, Peer Instruction is very effective in promoting student comprehension of course materials. The results of a 10-year longitudinal study conducted at Harvard University to explore the impact of PI on student learning compared to traditional lecture show an improvement in student mastery of both conceptual reasoning and quantitative problem-solving . In particular, the study reveals that the observed normalized learning gains with PI were regularly twice those observed with traditional lecture alone  & . Moreover, the mean score on the exam was, statistically, significantly higher in the course with PI compared with the traditional lecture. In addition to its positive impact on student learning, other empirical studies suggest that student’s retention and their ability to solve novel problems were significantly improved by the regular use of Peer Instruction activities .
Is Technology Necessary?
High tech is not necessary for successful Peer Instruction, but using technology such as iClicker or Google Slides does allow instructors to immediately view student responses both before and after the PI discussion. It is the pedagogy that improves student learning, though, not the technology. Low-tech tools such as flashcards can be used in PI activities and produce the same learning gain .
 Crouch, C. H., & Mazur, E. (2001). Peer instruction: Ten years of experience and results. American journal of physics, 69(9), 970-977.
 Lang, J. M. (2017). How Peer Instruction and Polling Have Changed My Teaching. The Chronicle of Higher Education.
 Peer Instruction. ABL Connect. Derek Bok Center for Teaching and Learning. Harvard University. Retrieved on Oct 27, 2019, from https://ablconnect.harvard.edu/peer-instruction-research
 Schell, J. (2013). Quick Start Guide to Flipping your Classroom with Peer Instruction. Turn to Your Neighbor “Official PI blog".Retrieved on Oct 27, 2019
 Vickrey, T., Rosploch, K., Rahmanian, R., Pilarz, M., & Stains, M. (2015). based implementation of peer instruction: A literature review. CBE—Life Sciences Education, 14(1), es3.
S. Dallal, University of Michigan