High school graduation rates are higher than they have ever been in 40 years, but disparities continue to exist for students of color and students from poverty when compared to their counterparts. High school reform efforts like creating small learning communities are promising, but small schools alone do not improve student outcomes. Personalization and responsive learning environments are essential to improving academic achievement in high schools, and particularly for ninth graders. A monocultural teaching force paired with a racially and culturally diverse student population necessitates an examination of teachers' awareness of cultural diversity particularly in the high school setting where inequities exist. This non-experimental, quantitative study of teachers' awareness of cultural diversity and academic achievement in ninth grade academies and senior high schools included 154 high school teachers from eight high schools in Mississippi. Descriptive statistics indicated that ninth grade academy teachers and senior high school teachers had similar levels of cultural diversity awareness. Both groups of teachers perceived that academic achievement growth remained the same over two years, and ninth grade academy teachers reported the dropout rate had decreased over two years. An analysis of archival SATP data revealed that the Black/White achievement gap was more prevalent in the participating ninth grade academies compared to ninth graders statewide. However, the gap between poor and affluent students was more prevalent among ninth graders statewide compared to students in the participating ninth grade academies. The results indicated that there was no significant relationship between teachers' awareness of cultural diversity and perceived academic achievement growth or perceived persistence in school as measured by perceived dropout rates. No statistically significant differences were found between ninth grade academy teachers' awareness of cultural diversity and senior high school teachers' awareness of cultural diversity. [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://www.proquest.com/en-US/products/dissertations/individuals.shtml.]