Research results from the past decade on the efficacy of online instruction for high school students varies. While many researchers suggested that younger students, mathematics students, and already struggling students who take online classes were underperforming compared to their classmates in the same course taken face-to-face (f2f), other researchers noted the advantages of online courses in providing flexibility, especially in pacing. Online education remains a popular course option for these learners despite the conflicting evidence of being able to truly support them in getting closer to graduation. Framed by Moore's transactional distance theory, a nonequivalent group quasi-experimental design was used to consider differences in student success and course completion between online and f2f environments for ninth-grade first-time Algebra I students while controlling for gender and ethnicity. Census sampling and logistic regressions were used to analyze archived data for 26,747 ninth-grade students who took Algebra I between 2016-17 to 2019-20 in the cooperating district's f2f or virtual courses, or the state-run virtual program. The independent variable consisted of the three environments while three dependent variables included (a) end-of-course final grades, (b) FastBridge aMath assessment results, and (c) completion as measured by course grade codes. Findings indicated that f2f students may have been outperforming online students, however, not all assumptions for analysis were met. This study may provide key information for improving both Algebra I and online education, increasing graduation rates, and better allocating funding in the educational budget. [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.]