Effect of Peer Mediated Instruction on Secondary School Students' Achievement in Biology

Abstract Poor achievement in Biology at Senior School Certificate Examination remains a challenge in Nigeria, with Ecology consistently identified as a difficult concept. Despite evidence that student-centered strategies can improve learning, there is limited empirical evidence on the effect of Peer Mediated Instruction on SS II students’ achievement in Ecology specifically within Enugu Education Zone, and findings on gender differences remain mixed. This study determined the effect of Peer Mediated Instruction on SS II Biology students’ achievement in Ecology in Enugu Education Zone, Nigeria. A quasi-experimental, pretest-posttest, non-equivalent control group design was adopted. The population comprised all SS II Biology students in coeducational public secondary schools in the zone. A sample of 120 SS II students from two intact classes participated. One class of 60 students was taught Ecology using Peer Mediated Instruction while the other class of 60 students was taught using Lecture Method for four weeks. Data were collected using a 30-item Biology Achievement Test in Ecology with reliability coefficient of 0.82. Findings revealed that students taught with Peer Mediated Instruction achieved significantly higher than those taught with Lecture Method, F(1, 117) = 44.904, p < .001, η² = .277. There was no significant gender difference, F(1, 87) = 2.900, p = .093. The study contributes evidence that PMI is an effective, gender-neutral strategy for teaching Ecology. It is recommended that Biology teachers adopt PMI and that Ministries of Education organize workshops to train teachers on its use. Keywords: Peer mediated instruction, achievement, ecology, biology, gender