The paper describes the launch of Peer-Led Team Learning for Precalculus Engineering and Math at the University of Texas at Arlington (UTA) and the results that PLTL has had on pass rates. Historically, students placed into Precalculus, instead of being Calculus ready, have experienced higher failure rates than any other student grouping. While UTA has invested in many studies, programs and techniques that aid these underprepared students, a few strategies have emerged as being effective. These strategies have included the previous implementation of Supplemental Instruction (SI), with separate sections devoted specifically to Precalculus co-enrolled engineering-course students, peer-based instruction, and active learning activities as opposed to additional lectures. As a result of these findings, in the Fall 2020 semester, UTA combined all these strategies into a learning course integrating these best practices into a required PLTL learning lab with problem-based activities and studying practices for the engineering course and a self-selected PLTL option for the math course. The goal was to aid in increasing success rates in these classes. The students engaged in effective “study habits” and problem-based learning practices with a Peer-Led Team Learning (PLTL) leader. What we have found is the positive impact that PLTL has on pass rates for at-risk populations in addition to positive satisfaction surveys. This paper will show the effectiveness of PLTL by discussing success rates for the Fall 2020 and Spring 2021 semesters versus the other singular implementations from previous semesters, in this case Supplemental Instruction.