Our study examines the impact of adult mentoring on Black, under-resourced, urban, middle grade students. First, we explore impact of mentoring on grades earned in the context of a comprehensive program which included one-on-one mentoring and an array of out-of-school enrichment activities. We also examine the nature of mentor-mentee engagement during mentoring interactions. Descriptive statistics were used to compare mean differences in grade point averages (GPAs) of students in the comprehensive program with those in the non-comprehensive (one-on-one mentoring only) program. Comprehensive Program mentees earned higher GPAs than non-comprehensive mentees overall in mathematics, reading, and science. Further, when reading GPAs of the groups were compared, the mean difference was statistically significant at the 0.05 level. An independent samples t-test for equality of means was also used to explore the impact of mentor-mentee engagement. Results from this examination highlighted the importance of the intensity and content of engagement during mentor-mentee interactions.