In Paper #1, I investigate the career exploration processes of 96 recent graduates of elite higher education institutions with varying levels of interest and commitment to teaching. My aim is to understand how intrinsic motivations to teach (positive) and extrinsic concerns about teaching (negative) are developed and interact such that some academic high achievers choose to teach while others do not. I find that motivations to teach were often developed through engaging in teaching-related activities, participating in education-related academic experiences, and reflecting on the impact of teachers. I also find that while extrinsic concerns about teacher pay, prestige, and career advancement were ubiquitous, what distinguished academic high achievers who chose to teach was that they held beliefs that specifically addressed their extrinsic concerns and that these beliefs were often developed through conversations with other academic high achievers who chose to teach or supported teaching as a career. These findings suggest the possibility of attracting more academic high achievers into teaching through policies that develop their intrinsic/altruistic motivations and/or foster beliefs that directly address prevalent extrinsic concerns. Paper #2 is a narrative inquiry drawing on the same dataset as Paper #1. My aim is to examine how academic high achievers learn through explicit and implicit signals that teaching is not appropriate for someone like them. I show that the process is social, with parents and peers playing a significant role in shaping beliefs. These findings suggest that policy efforts to recruit more high achievers into teaching may benefit from focusing earlier in the career exploration pipeline. Paper #3 is a systematic literature review of the research designs and measurement approaches of 166 causal evaluations of teacher preparation practices published in peer-reviewed journals between 2002-2019. Although I find that very few studies address issues of internal validity, external validity, and measurement, I highlight some innovative approaches as guidance for future researchers. I also present a common template for designing and reporting on causal evaluations of teacher preparation practices. [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.]