This aims of this research were to examine the personal, behavioral, and environmental factors, as outlined in Social Cognitive Career Theory, of 12th grade females in the United States. Specifically, this study examined the student factors that influence career goals and academic performance for females in science, technology, engineering, and mathematics (STEM) for female populations traditionally overrepresented (White, Asian) and underrepresented (Black, Latinx, Native Hawaiian/Pacific Islander, Native Alaskan). Data used in this study were from the 2015 science questionnaire for students from the National Assessment of Educational Progress (NAEP). Using the Social Cognitive Career Theory framework, secondary analysis of NAEP data sought to understand why some females enter STEM fields at drastically higher levels than others. Results from descriptive statistics, linear regression, and path analysis showed significant differences in the role of self-efficacy for underrepresented females and their choice goals and academic performance compared to overrepresented females. Both overrepresented and underrepresented females had significant relationships between learning experiences and outcome expectations, as well as outcome expectations and choice goals, among other findings. Implications for these findings are discussed. [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.]