Assessing student success in a Peer Assisted Learning program using propensity score matching

Abstract

The Peer Assisted Learning program at Sacramento State University (PAL) was established in 2012 with one section supporting introductory chemistry. It now serves 17 gatekeeper courses in Biology, Chemistry, Mathematics, Physics, and Statistics, enrolling approximately 1,400 students annually. Adapting the Peer-Led Team Learning model, PAL Facilitators do not teach, tutor, or even confirm answers; they do ask scaffolding questions, provide encouragement, and ensure that all group members participate in problem-solving. Here we assess the efficacy of the program in terms of student success in the parent course. As PAL is an opt-in program, we employ propensity score matching techniques to account for confounding factors. Our analysis of 11 classes shows that PAL provides an average course GPA bump ranging from .23 to .71 grade points (mean .42). Compared to the non-PAL baseline course GPA, this amounts to an increase of 9% to 51% (mean 23%). We consider data from over 25,000 students, and our propensity score analysis uses over 10,000 students (4,519 PAL, 5,814 non-PAL) for whom appropriate matches could be found.