Effect of Problem-Based Learning on Secondary School Chemistry Students’ Achievement in the Law of Electrolysis, Oyo Town

This study examined the effect of Problem-Based Learning (PBL) on secondary school chemistry students’ achievement in the Law of Electrolysis in Oyo Town, Nigeria. Despite the importance of chemistry as a foundational science subject, students’ performance in topics like electrolysis has persistently remained low, attributed to its abstract nature and the predominance of conventional, teacher-centered instructional strategies. A quasi-experimental design, involving non- equivalent control and experimental groups with pre-test and post-test measures, was adopted. A total of 58 Senior Secondary II Chemistry students from two purposively selected public secondary schools participated in the study. The experimental group received instruction through PBL, while the control group was taught using the traditional lecture method. Data were collected using the Electrolysis Accomplishment Test (EAT) and analyzed using Analysis of Covariance (ANCOVA). The results revealed a significant main effect of PBL on students’ achievement in the Law of Electrolysis (F (1, 55) = 8.043, p < 0.05, η2 = 0.838), with students in the PBL group outperforming those in the control group. Additionally, a significant interaction effect of teaching method and gender was observed (F (1, 53) = 43.944, p < 0.05, η2 = 0.914), though the gender-based performance difference within each group was not statistically significant. The findings affirm the effectiveness of PBL in enhancing students’ conceptual understanding and academic performance in challenging chemistry topics, regardless of gender. The study recommends integrating PBL into secondary school chemistry curricula and promoting the professional development of teachers in learner-centered instructional approaches.