Despite ongoing efforts to reform schools, the longstanding racial/ethnic achievement gap still persists, particularly for boys of color; in many cases, the gap is widening, particularly for students transitioning from elementary to middle school. The focus of this study was to examine the impact of effective instructional practices for struggling eighth-grade readers, and how these practices can help bridge the achievement gap among students from diverse backgrounds. This study utilized correlational research methods to determine the relationship between teacher qualities and instructional practices and the reading achievement of struggling eighth-grade students. The study used national data from the 2013 NAEP Eighth Grade Reading Assessment, including test scores. The researcher focused on 80 variables from the teacher and student surveys from 170,600 public schools and 151,777 teachers. Factor analysis was used to create factors; then statistical linear regression models were created to determine whether a significant relationship existed between the variables and the overall sample and subpopulations. Three conclusions were made. First, there is a statistically significant relationship between teachers' professional and instructional training and student reading achievement at the middle school level. Second, a statistically significant relationship exists between a teacher's classroom practices and eighth-grade reading achievement. Third, there is a statistically significant relationship between teacher qualities on student reading achievement for the independent variables of race/ethnicity, gender, and socioeconomic status. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]