During the 2020 spring semester, the MIT Physics Department introduced a mentoring component into the second half of 8.02, a large first-year undergraduate class in electromagnetism. One goal was to help students who were struggling after the first exam to successfully pass the course and to develop skills needed for success in other challenging classes. Another stated goal was to enhance students' self-efficacy, STEM identity, and integration of their social and other identities within the MIT cultural setting. The program met and exceeded its goals. The materials below provide detailed information about the program including implementation, training materials, assessment, and outcomes.