This study explored the impact of a learner-centered, mid-semester course evaluation process called the small group instructional diagnosis (SGID) on student perceptions of dimensions of teaching that promote effective learning. Classes where instructors requested the SGID were randomly assigned to either traditional or learner-centered SGIDs and then students from these classes were surveyed at the end of the semester. Results reveal that the SGID process, independent of format, favorably affects student perception of the overall learning environment. However, the learner-centered SGID had a significantly higher impact on student perceptions of select dimensions of teaching including understanding of course assignments and tests, interactions with classmates, course preparation, motivation to excel, and enthusiasm. Moreover, students in the learner-centered group were significantly more likely to report positive changes in their own behaviors following the SGID.