This study investigated the possible effects the use of charts might have on students’ understanding of the concept of mensuration using demonstration and collaborative instructional approaches. Two research questions and two null hypotheses guided the study. The quasi-experimental research design was employed to conduct the study. A sample of 105 drawn from a population of 800 senior secondary two students in Okrika Local Government Area of Rivers State Nigeria. The instrument used to collect data was Test on Understanding of the Concept of Mensuration (TUCM). TUCM was validated and the KR-20 formula was used to establish a reliability of .86. The research questions were answered descriptively using mean, standard deviation, and graph while the hypotheses were tested inferentially at .05 level of significance using Analysis of Covariance (ANCOVA). The result showed that students taught using demonstration instructional approach with chart understood the concept of mensuration better than those taught with collaborative approach with chart. There was also a significant difference between the mean gain of students taught using demonstration approach with chart and those taught using collaborative approach with chart. There was no significant difference between male and female students’ understanding of the concept of mensuration when taught with chart using demonstration and collaborative approaches. It was recommended among others that mathematics teachers should teach mensuration with charts using demonstration approach.
Keywords: Mean Grand Score, Post-Test, Pre-Test