This quantitative non-experimental inferential research assessed the influence of teachers' cultural competences (CQ) on the academic achievement in diverse school populations. The education of people of color or the impoverished of any ethnic groups has been a perennial problem contributing to persistent gaps in the academic achievement of diverse student populations. The literature confirmed teachers' CQ was a valid epistemological and ecological construct that may influence academic achievement. Few studies analyzed the influence of teachers' cultural competencies on academic achievement. This study sought to equip schools and teachers with knowledge of cultural variables that influence academic achievement. The research site was a mid-sized school in Youngstown, Ohio. Due to data collection limitations, only 26 teacher surveys informed the analyses. The instrument to assess teachers' CQ was the Expanded Cultural Intelligence Scale (E-CQS). The E-CQS uses four domains: behavioral, cognitive, metacognitive, and motivational to assess individual's overall CQ. Teaches were ranked as having a high or low CQ score. Teachers' CQ was the independent variable. Comparative student data, the dependent variables, was the 1st and 2nd semester grades of students. Four hypotheses tested the influence of teachers' CQ on students' net difference in 1st and 2nd quarter grades. Behavioral, cognitive, and motivational CQ had no statistically significant influence on students' grades. Metacognitive CQ had a statistically significant influence on students' grades. The implications of this study should influence educators and universities that train educators. If schools conduct assessments of teachers regularly, are they leaving out assessing teachers' cultural competencies? Stakeholders should make necessary realignments to support teachers in developing cultural competencies needed by students. [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.]