Science, technology, engineering, and mathematics (STEM) education is an economic opportunity for an urban school district in Tennessee. Lack of interest in STEM courses was throughout schools with underrepresented populations. An urban district in Tennessee with few schools implementing STEM initiated instructional practices to increase achievement for African Americans in math and science classes. The purpose of this quantitative, non experimental, ex post facto study was to examine the impact of STEM instructional practices on post-assessments among African Americans. More specifically, the study examined how African Americans performed in Algebra I and Biology after receiving instruction with components of STEM pedagogical practices. To assess the impact of the STEM instructional practices, this study analyzed district data from content-specific post assessments in Biology and Algebra I from the fall assessment. An analysis of the assessment data utilizing a one-way analysis of covariance was conducted controlling for preassessment scores from the fall. An independent-samples t-test for Algebra I was also run to determine if there were differences in post-assessment scores between schools that utilized STEM instructional strategies and schools that did not use STEM instructional strategies among 9th- and 10th grade students enrolled in Biology. The findings minimally showed a difference in students receiving STEM instructional practices in Biology. While controlling for the preassessment scores, there was, however, a significant difference in post-assessment scores based on the instructional practices utilized in Algebra I. The data suggested when a school utilized STEM instructional practices in Algebra I, underrepresented students received higher scores on Algebra I assessments. The findings from this study revealed the value of STEM instructional practices and the importance of more expanded research. [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.]