By using a quasi-experimental design, in this study, we test the effect of undergraduate teaching assistants on student learning. Data were collected from 170 students enrolled in four sections of a quantitative research methods course, two sections without undergraduate teaching assistants and two sections with undergraduate teaching assistants, over two semesters. Results indicate that having undergraduate teaching assistants in the classroom can result in higher student performance. Students in the sections with undergraduate teaching assistants earned higher grades, were more likely to pass the course with a C or higher and performed better on half of the student learning outcomes than students in the sections without an undergraduate teaching assistant. Based on the overwhelmingly positive results on student learning, we would recommend the active use of undergraduate teaching assistants in the classroom, but especially for courses that students find challenging.