Supplemental Instruction (SI) is today a well-known academic assistance program that provides help for students in "difficult" courses. SI has repeatedly been shown to decrease the percentage of failures in the course as well as increasing course grades for students who attended SI sessions. Although SI is open for all students, its main objective is to come to terms with students' high failure rates and retention problems. And even if SI has been shown to reduce failure rates and increase re-enrollment figures, surprisingly few studies have been devoted to determine how well it benefits students with different prior academic ability. These studies tend to show that "weaker" students benefit from SI. The results for "average" and "strong" students are not as clear. The present study focuses on the benefit of SI for "weak", "average," and "strong" first-year engineering students in a calculus course. The results show that all three groups benefit from SI and that the failure rates among students with low prior mathematics achievement who had high SI attendance are almost as low as for students with high prior mathematics achievement who do not attend SI. (Contains 4 tables and 2 figures.)
