This experimental study investigated the effects of group size on students’ mathematics achievement in small group settings. Two third year classes studying General Art were selected from two schools in the Central Region of Ghana for the study. The rational for the selection of these classes is that traditionally these have been classes whose students do not show interest in the study of mathematically based subjects and that they might not be very much different in mathematics performance. The two classes constituted the control and experimental groups respectively and consisted of 50 students in the control group and 47 in the experimental group. The experimental group was subdivided into 12 groups made up of groups of 3 members, groups of 4 members and groups of 5 members using stratified and simple random sampling. The students’ pre- and post-test scores served as the data for the study. The results showed that after approximately 12 weeks, students’ who were instructed using small group cooperative learning achieved a significantly higher scores on the achievement posttest then those taught by the conventional method of instruction. However, the study also revealed that there was no statistically significant difference in the mean scores of the three subgroups of the experimental group. The study therefore support that, group size is less important in what the group actually does
Keywords: Achievement, Cooperative learning, Group size
