Vol. 8, Issue 1, Part A (2026)

This study investigates the comparative effectiveness of peer teaching and expository teaching methods on the academic performance of Grade 8 students in Mathematics at a secondary school in Region 6, Guyana. Using a quasi-experimental design, two groups of students with comparable baseline abilities received instruction through either peer teaching or traditional expository methods, guided by detailed lesson plans. Pre- and post-tests measured learning gains, while statistical analyses evaluated differences in outcomes. Results showed that both groups improved significantly from pre-test to post-test. The expository group’s mean score increased from 9.33 (23.33%) to 26.13 (65.31%), reflecting a 42%-points gain. The peer teaching group, however, achieved a greater improvement from 9.25 (23.13%) to 30.75 (76.88%), a 53.75 percentage point increase. The difference in post-test performance between groups was statistically significant (t=-8.26, p<0.001), indicating superior academic achievement with peer teaching. Additionally, the peer teaching group’s higher variance suggested wider individual gains and deeper engagement. While both groups began at similar knowledge levels, only the peer teaching group reached a "good" performance category post-intervention, surpassing the expository group’s "satisfactory" level. These findings support the hypothesis that peer teaching promotes enhanced understanding, retention, and student confidence compared to traditional direct instruction. The findings highlight the benefits of interactive, student-centered learning environments while acknowledging the role of structured teacher-led instruction, thereby informing best practices for improving mathematics achievement among Grade 8 learners.