The Effect of Supplemental Instruction on Student Performance

Supplemental Instruction (SI) is a practice of providing peer-assisted academic support for historically difficult courses in universities in the US and across the world. According to the Department of Education, participation in SI improves the course grade, likelihood of course completion, and students’ overall retention rates at the university. Research studies have also found evidence consistent with these claims. However, majority of the studies fail to account for the problem of selection of students into SI participation. To overcome this selection bias, we use administrative data from a mid-sized public university in Texas and exploit the within-course variation in SI offerings arising from factors like administrative changes, lack of funding, or inability to match an SI leader to a course. Results from intent-to-treat models indicate small positive effects on course GPA or likelihood of course completion for the overall population. The benefits of SI are larger for subgroups of female students, students with below median SAT/ACT scores, and juniors and seniors