In recent years, a great deal of emphasis has been placed on increasing students' interest in math and science. Specifically, interest in science, technology, engineering, and math (STEM) has been low among students in the United States, and interest seems to be lower among girls than boys. Additionally, increased emphasis has been placed on increasing female representation in STEM careers, as numbers of women in these fields remains disproportionately low compared to men. A variety of factors have been found to increase young people's interest in STEM, including parent and teacher factors, informal STEM experiences, self-efficacy in math and science, and individual differences such as curiosity and persistence. Previous research also indicates, however, that women may face specific barriers in STEM training related to their gender. The current study was an attempt to examine how predictors of STEM interest relate to each other and serve as predictors of pursuing a career in STEM. Further, the current study examined how pathways between these variables differ by gender. Finally, the current study explored the barriers experienced by students pursuing careers in STEM in an attempt to identify factors that deter women from entering these professions. For both men and women parental educational involvement predicted higher frequency of informal STEM learning experiences and lower ratings of persistence. For men only, parental educational involvement predicted higher curiosity and higher curiosity predicted lower persistence. For both men and women, higher frequency of informal science experiences predicted higher self-ratings of curiosity. For women only, frequency of informal science learning experiences in childhood was predictive of higher STEM self-efficacy. For both men and women, positive math and science high school teacher influence predicted higher curiosity as well as higher STEM self-efficacy. For women, math and science teacher influence was also predictive of higher likelihood of career selection involving STEM, whereas for men only, childhood informal science learning experiences were predictive of higher likelihood to pursue a STEM career. Lastly, higher likelihood of STEM career selection was predicted by higher ratings of STEM self-efficacy for both men and women. Exploratory models examining the influence of inquiry-based learning (IBL) experiences in high school science classrooms indicated that IBL predicted higher curiosity, STEM self-efficacy, and intentions to pursue a STEM career for both men and women. For women only, higher frequency of IBL in high school was predictive of lower self-ratings of persistence. This study adds to the current literature examining predictors of STEM career choice and explains how parental and family factors, school factors, and individual differences interact to explain differential pathways to STEM career interest for men and women.