The Effect of Concept Mapping on Students' Academic Achievement in Physics in Secondary Schools in Nasarawa State

Physics achievement among Nigerian senior secondary school students has remained persistently weak, a pattern frequently linked to the continued dominance of the conventional lecture method and to the abstract, hierarchically structured nature of physics concepts, which many students struggle to organise meaningfully. This study empirically investigated the effect of concept mapping on the academic achievement of secondary school students in Physics in Nasarawa State, using electricity and magnetism as the substantive content area. A quasi-experimental, non equivalent control group design with a pretest-posttest structure was adopted. A multi-stage random sampling technique was used: one Local Government Area was randomly selected from each of Nasarawa State's three senatorial zones (Nasarawa North, Nasarawa South, and Nasarawa West), one senior secondary school offering Physics was then randomly selected from each selected Local Government Area, and intact Senior Secondary Two (SS2) Physics classes within each school were randomly assigned to experimental (concept mapping) and control (conventional lecture method) groups, yielding a total sample of one hundred and eighty (180) students. To assess the wider national plausibility of the study's findings, an illustrative cross validation exercise involving Physics education staff and students was additionally conducted at one polytechnic randomly selected from each of Nigeria's six geo-political zones. Data were collected using a researcher-developed, expert-validated, twenty-five-item multiple-choice Physics Achievement Test (PAT), with a Kuder-Richardson (KR-21) reliability coefficient of 0.81, and analysed using mean, standard deviation, and Analysis of Covariance (ANCOVA), with pretest score as covariate, at the 0.05 level of significance. Results showed that students taught electricity and magnetism using concept mapping achieved significantly higher mean posttest scores than those taught using the conventional lecture method, F(1,177) = 41.53, p < .05, and that there was no statistically significant interaction effect of teaching method and gender on Physics achievement, F(1,177) = 0.97, p > .05. The study concludes that concept mapping significantly and equitably enhances Physics achievement among secondary school students in Nasarawa State, and recommends its wider adoption in Physics instruction, alongside structured teacher training in concept-mapping facilitation.