The general problem in this study was that African American high school students were failing mathematics at staggering rates due to standardization of non-inclusive math curriculums, void of a math pedagogy. Curriculums should be based on the ideals of SDT that inspire intrinsic and extrinsic motivation. The specific problem in this study was that limited knowledge had been established regarding the effective components of the SDT that would inspire intrinsic and extrinsic motivation needed for African American students to learn mathematics. The purpose of this qualitative case study was to explore what types of intrinsic and extrinsic motivating strategies were being used by African American ninth-grade students to comprehend mathematics and sustainably achieve in a Title I private school located in West Georgia. The intrinsic and extrinsic aspects of the SDT showed the importance of understanding African American students' academic motivational behaviors to learn mathematics sustainably. A qualitative approach was used to investigate and analyze the integral parts of the SDT believed to increase African American students' math achievements. This study was administered for five months (i.e., a complete semester) in an urban private school in western Georgia for African American high school students. Individual pre-interview scripts, questionnaires, and postquestionnaires were conducted with 15 ninth-grade students. All participants completed the postquestionnaire to corroborate information further from the interview and student questionnaires. The data were manually evaluated from interviews and questionnaires for patterns, themes, and categories. The findings of the coding process based on the research questions showed nine themes: (a) motivation inspires the SDT, (b) intrinsic and extrinsic motivation founded in the SDT, (c) intrinsic and extrinsic motivation engages students, (d) making intrinsic and extrinsic motivation accessible, (e) ensuring motivating math practices, (f) motivation and academic achievement, (g) motivation and academic achievement for African American learners, (h) academic achievement and extrinsic motivation, (i) academic achievement and intrinsic motivation, (j) motivation promotes achievement attitudes, (k) motivating strategies promotes self-regulated behaviors, and (l) promoting math excellence. The study's discovery was assessed based on applicable literature and preceding research, showing details to corroborate how and in what ways the themes from this study were reinforced by the literature. The findings revealed recommendations for subsequent research. A future researcher may study students from an urban private school attending a Title I math class based on low academic performance, low test scores, and socio-economic factors for ninth-grade African American students to expose intrinsic and extrinsic motivating instructional strategies. According to admissible research, an acknowledgment of SDT-based intrinsic and extrinsic motivating strategies may enable ninth-grade African American students to become proficient math learners (Boberg & Bourgeois, 2016a). However, finite research prevails about the types of effective motivating strategies for African American children (Ukpokodu, 2011). Moreover, this category of research can yield awareness and advocacy for the SDT. Future research may also include comparing the effectiveness of either intrinsic or extrinsic motivation (Martin, 2012). Present-day researchers can qualitatively reveal how African American students can become increasingly motivated to comprehend mathematics and excel based on intrinsic and extrinsic motivating strategies (Meshack, 2013). [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.]