This study investigated the influence of class size on students’ academic achievement in public secondary schools in Niger North Senatorial District, Niger State, Nigeria. The study examined how large, normal, and small class sizes affect students’ academic achievement. A descriptive survey research design was adopted. The population comprised 4,025 respondents, consisting of 68 principals and 3,957 teachers from 68 public secondary schools in the district. Using a simple random sampling technique, a sample of 405 respondents (9 principals and 396 teachers) representing 10% of the population was selected. Data were collected using a structured questionnaire titled Questionnaire on the Influence of Class Size on Students’ Academic Achievement, and a pro forma for students’ academic records. The instrument was validated by experts and its reliability established through a pilot study. Descriptive statistics (mean and standard deviation) were used to answer the research questions, while Chi-square statistics were employed to test the hypotheses at 0.05 level of significance. The findings revealed that large, normal, and small class sizes have significant influence on students’ academic achievement in public secondary schools in the study area. The study concluded that class size is a critical factor in effective teaching and learning. It was recommended that government and educational authorities should strictly adhere to the National Policy on Education teacher student ratio of 1:30 through the recruitment of qualified teachers and provision of adequate classroom facilities among others.
Keywords: Academic Achievement, Public Secondary Schools, Teaching and Learning, class size
