This study examined whether having African-American middle school students write essays affirming their personal values improved their academic performance. The study analyzed data on about 175 African-American and 190 European-American students (the study's term for white students who are non-Latino and non-Asian) at a suburban middle school who were randomly assigned to intervention and comparison groups at the beginning of seventh grade. The study measured effects by comparing the seventh- and eighth-grade GPAs of students in the intervention and comparison groups. These GPAs included grades from the four core academic subjects: science, social studies, math, and English. The study examined effects separately for European-American and African-American students and for low- and high-achieving students. Among African-American students, completing writing exercises about their values increased their average seventh- and eighth-grade GPA by a quarter of a letter grade (0.24 points), a change that was statistically significant. The intervention did not have a statistically significant effect on the academic outcomes of European-American students. Among low-achieving African-American students, the effect was somewhat larger, an increase in average seventh- and eighth-grade GPA of 0.41 points. In addition, the intervention reduced the likelihood that low achieving African-American students were assigned to a remedial program or were retained in grade. The research described in this article is consistent with WWC evidence standards. This study was a well-implemented randomized controlled trial. [The following study is reviewed in this What Works Clearinghouse Quick Review: Cohen, G. L., Garcia, J., Purdie-Vaughns, V., Apfel, N., & Brzustoski, P. (2009). Recursive processes in self-affirmation: Intervening to close the minority achievement gap. "Science, 324(5925), 400-403".]