Despite considerable public attention to STEM teacher shortage, little research has been done on the STEM teacher pipeline. This dissertation compares STEM majors with an interest in secondary school teaching (hereafter referred to as STEM teachers), STEM majors without an intention to enter secondary school teaching (hereafter referred to as STEM majors), and students with an interest in secondary school teaching (hereafter referred to as secondary school teachers). In this dissertation, I investigate individual, family, and institutional variables associated with students’ plans to enter STEM majors and pursue a career in education. I utilize Social Cognitive Career Theory (SCCT) framework to understand the major selection process of traditional age, first-year students beginning their undergraduate studies at four-year colleges and universities in the United States. I employ descriptive statistics and a series of logistic regression models using data from the Higher Education Research Institute (HERI) Cooperative Institutional Research Program’s (CIRP) American Freshman Surveys. Several important findings emerged but in summary, this dissertation sheds light on the variables associated with interest in STEM teaching and provides both recent and historical empirical evidence related to interest in STEM teaching, and provides directions for future policy and research.