Effect of an Improvised Plant Cell Model on The Academic Achievement of Secondary School Students in Biology in Minna, Niger State

Abstract

Persistent underperformance in biology among Nigerian secondary school students, particularly in abstract topics such as cell structure, necessitates innovative pedagogical approaches. Conventional lecture-based methods often fail to facilitate conceptual understanding of microscopic biological structures, contributing to poor academic achievement. This study investigated the effect of an improvised plant cell model on the academic achievement of secondary school biology students in Minna Metropolis, Niger State, Nigeria. A quasi-experimental (pretest-posttest control) group design was employed with 256 Senior Secondary II (SSII) biology students randomly assigned to experimental (n = 119) and control (n = 137) groups. The experimental group received instruction using an improvised plant cell model constructed from locally available materials, while the control group received conventional lecture-based instruction. Data were collected using the Improvised Plant Cell Model Test (IPCMT), a 30-item multiple-choice instrument with established reliability (r = 0.88). Analysis of variance (ANOVA) was used to test hypotheses at α = 0.05. The experimental group demonstrated greater improvement in mean achievement scores (mean gain = 10.35, SD = 5.55) compared to the control group (mean gain = 2.98, SD = 4.65). ANOVA confirmed a significant difference in post-test scores between groups, F (1, 254) = 123.310, p < 0.005, η² = 0.327, indicating a large effect size. While female students in the experimental group showed slightly higher mean gains (mean gain = 11.81) compared to males (mean gain = 10.06), this difference was not significant, F (1, 117) = 3.233, p = 0.075. The improvised plant cell model significantly enhanced students' academic achievement in biology compared to conventional teaching methods, with benefits across genders. This study provides empirical support for integrating hands-on, model-based instructional strategies in resource-constrained educational settings.