Underrepresentation of ethnic minorities in science, technology, engineering, and mathematics (STEM) fields has been a growing concern. Efforts to ameliorate this have often been directed at college-level enrichment. However, mentoring in the sciences at a high-school age level may have a greater impact on career choices. The Center Scholars Program prepares gifted minority students for participation in college-level research while they are still in high school. Results from a case/comparison group study demonstrated that 86% of Center Scholars, compared to 50% of the comparison group, plan to pursue a career in science research, suggesting that high-school enrichment programs have a substantial impact on minority participation in science and research fields. (Contains 5 tables.)