Effect of the Use of Instructional Materials on Senior Secondary School Students’ Achievement in Biology in Oyo Metropolis, Oyo State

The abstract nature of respiratory physiology, combined with limited hands-on experiences and interactive learning opportunities, impedes students’ understanding and retention of crucial concepts. Furthermore, the inadequate access to high-quality instructional materials exacerbates the issue, leaving students without sufficient resources to supplement their classroom learning. This study therefore investigated the effects of standardized and improvised instructional materials on the academic achievement of Senior Secondary School Biology students in respiratory system topics in Oyo Metropolis, Nigeria. This study was based on constructivism and cognitive theories and utilized a Quasi-experimental research design. The study population consisted of 13,716 senior secondary school students in Oyo Metropolis. A purposive sampling technique was employed using intact classes of 149 SSS 11 students. Biology Achievement Test (BAT) (KR20 =0.8) was used as instrument for data collection. Three hypotheses were formulated at 0.05 level of significant and data were analyzed using Covariance (ANCOVA). The findings revealed that improvised instructional materials has a significant main effect on students’ academic achievement in Biology (F(1;144) = 46.627; P-value