Abstract

This study investigated concrete geoboard manipulatives and junior secondary school students’ performance in plane geometry in Port Harcourt, Nigeria. Three research questions and hypotheses were answered and tested. Quasi-experimental research design, specifically focusing on intact classes was utilized. The research population consisted of 4,554 Junior Secondary School one (JSS1) students from twenty-four public schools. The researcher employed purposive sampling to select a group of 151 JSS1 students for the study. Data was gathered using the Plane Geometry Achievement Test (PGAT), which consisted of 20 multiple choice questions. The instrument was subjected to face and content validity by three experts in the field of mathematics education. Kuder Richardson formula 20 statistic was used to establish an internal consistency of 0.73 for the instrument. Lesson plans were meticulously crafted for both the experimental and control groups to cater to their specific needs and learning objectives. Lesson plan that incorporated concrete geoboard manipulatives and lesson plan that incorporated charts. In order to gather data, both groups of students were given a preliminary PGAT assessment. Following this, the experimental group received instruction on perimeter and area of quadrilaterals using hands-on geoboard manipulatives, while the control group learned the same concepts through visual aids such as charts. Following the intervention for each cohort, a follow-up assessment was conducted with both sets of participants. The research questions were addressed using mean and standard deviations, and the null hypotheses were tested through Analysis of Covariance with a significance threshold of 0.05. The results indicated that students who received instruction in plane geometry using geoboard manipulatives outperformed those who were taught with chart-based methods, with a significant variance in scores. It is worth noting that male students in the experimental group showed greater academic success compared to their female counterparts, although this variance did not reach statistical significance. Furthermore, the male students who received instruction using charts outperformed their female counterparts with a statistically significant margin. Among the recommendations provided was the use of concrete geoboard manipulatives as a teaching tool for plane geometry.