The evaluation of secondary school systems in South Africa is essential for improving educational outcomes. A meta-analysis approach will be employed, including systematic review of existing studies on secondary school performance evaluations using quasi-experimental designs. The analysis revealed a significant positive correlation (r = 0.75) between the use of quasi-experimental designs and improved educational yield in South African schools, with over 60% of reviewed studies showing improvement trends. Quasi-experimental designs offer a robust method for evaluating secondary school systems in South Africa, contributing to more accurate and reliable performance assessments. School administrators should consider adopting quasi-experimental design methodologies in their evaluation processes to enhance educational yield. secondary schools, South Africa, quasi-experimental design, educational yield improvement, meta-analysis