This study explores the high academic achievement of Excelencia Early College High School (EECHS), located along the Texas-Mexico border. An open-enrollment public school, EECHS serves students who are characteristic of the lower Rio Grande Valley. These include students of low socioeconomic backgrounds, minorities, first-generation, and those typically underserved by higher education. Over two years, seven student focus-group interviews and fifteen faculty personal interviews were conducted. These interviews addressed key research questions such as: What are the lived experiences of students and faculty at this high-achieving school? What motivates students to overcome challenges and persist to graduation? What factors contribute to student success? How do teachers and faculty maintain the rigor required of college-level work? Results revealed multiple success factors, including a skilled teaching staff with high expectations and strong emotional support, an environment promoting student belonging through clubs and extracurricular activities, use of the AVID college preparatory program that teaches college readiness skills such as time management, self-monitoring, organization, and other types of essential skills for college success, and systems employed by the school to ensure student induction and progress, including Summer Bridge and self-reporting of grades. The early college high school reform movement gained momentum from the Early College High School Initiative (ECHSI), sponsored in 2002 by the Bill and Melinda Gates Foundation. This initiative aimed at bridging academic performance gaps through smaller schools and accelerated instruction for underserved populations. Texas has adopted this school reform model statewide, partly inspired by state demographer Steve Murdock. Efforts like Closing the Gaps (2000-2015) and 60X30TX demonstrate Texas's commitment to improving postsecondary outcomes for all its citizens. [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.]