Even though the United States includes college readiness as a national policy priority, little is known about the factors and experiences that determine positive outcomes in mathematics using online instruction for historically underrepresented minorities at 4-year colleges and universities. The purpose of this quantitative ex-post facto study was to investigate and evaluate the differences between students learning mathematics via online and on-ground modalities at a university in Alabama with a population consisting of predominately minority students. This study consisted of 200 students of both genders who enrolled in prerequisite math courses either on-ground or online. This study used archived data from a southern university comprised of approximately 90% minority (non-white) older than 18 years to examine learning through the theoretical lens of andragogy (adult learning theory). The differences in math achievement (test scores) and persistence (dropout rates) for online and traditional lecture-based (on-ground) modality were analyzed through the use of descriptive and multivariate statistics. The on-ground averages of the students slightly outpaced the online averages by 0.2439 (6.1%) grade points (on a 4.0 scale). The results of the one-way ANOVA for student performance indicated no significant differences among the grade scores (F(1, 144) = 1.039, p = 0.310). Online courses accounted for 83.3% of the total students withdrawing from all math courses sampled. The outcome of the study extended the current knowledge in math delivery revealing the need to find ways to mitigate poor math performance and decrease course dropout rates. The implications for future policy and research call for increased study and implementation of improvements to instructional delivery and design elements necessary for improved math achievement. [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.]