Educators, administrators, and policymakers focus much attention on closing the achievement gap, and various approaches have been suggested. The present study focuses on one approach being suggested: student-teacher ethnic matching. The study focused on the long-term contributions of African American ethnic matching to mathematical test scores of 1,200 African American students from the Early Childhood Longitudinal Kindergarten--fifth data set. Employing a two-level growth model, this study of impact from student-teacher ethnic matching revealed that a student having at least one teacher who ethnically matched themselves between kindergarten and fifth grade had a significant impact on mathematics achievement. (Contains 3 tables.)