Research suggests that the presence of peer mentors in Introductory Psychology classes can improve student performance by raising course completion rates, promoting achievement of student learning outcomes (SLOs), and elevating overall grades (Asgari & Carter, 2016). Accordingly, Psi Beta student researchers brought honors psychology students into Introductory Psychology classrooms to serve as peer mentors. These mentors delivered three online lessons through Zoom, which covered scientific reasoning, biopsychology, and antidepressant therapy. The present study evaluated the effectiveness of these peer-presented lessons through a 64-item post-presentation assessment pertaining to Introductory Psychology. A total of 73 undergraduate psychology students from Irvine Valley College completed the assessment, with a control group of 64 participants and a treatment group of 9 students who participated in the supplemental Zoom lessons for extra credit. It was hypothesized that students who completed the supplemental lessons would score higher on the assessment than students who did not complete the supplemental lessons. A subset of hypotheses was posed that the treatment group would score higher on three individual SLO’s compared to the control group. These SLO outcomes encompassed the following abilities: First, recall of various fundamental concepts presented in Introductory Psychology, second, the application of critical thinking to differentiate between psychological misconceptions and truth, and third, the ability to recognize different research designs, and formulate conclusions based on data. Results indicated no significant differences between the groups on the overall assessment nor the individual student learning outcomes. Limitations include group sizes, potential bias in the treatment group, and reduced impact of online learning compared to in-person instruction. Future research should compare the relative effectiveness of live in-person lesson delivery, live Zoom sessions, on-demand pre-recorded lectures. Results from this study can be used to further enhance psychology instruction and ensure that students comprehend course content while simultaneously providing growth opportunities for peer mentors.