Science, Technology, Engineering, and Mathematics (STEM) are key drivers of a fast-changing world and provide skills to solve challenges in such an environment. Adolescence, especially the high school-to-college transition, is characterized by large divergences in youth's STEM pathways, but the reasons for this divergence remain unclear (Riegle-Crumb et al., 2012). One of the goals of the proposed dissertation is to explore critical points (e.g., high school experiences) and places (e.g., neighborhood-based institutional resources) during high school and how they may contribute to youth's STEM pursuits in college, including a certificate or degree. Moreover, in this racial-ethnic stratified society, Black and Latinx youth, racial-ethnic minority groups, experience multidimensional disparities in STEM (Garcia Coll et al., 1996; Xie et al., 2015). Thus, I will examine whether racial-ethnic minority status moderates the link between youth's STEM pursuits and critical points and places. I will analyze these relationships using multilevel models to investigate what factors shape these relationships. Findings will broaden the understanding of the importance of critical points and places in the STEM pathway during the high school-to-college transition for youth from diverse racial-ethnic backgrounds. [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.]