Problem: An increasing number of high-achieving American high school students are enrolling in multiple Advanced Placement (AP) courses. As a result, high schools face a growing need to understand the impact of taking multiple AP courses concurrently on the social-emotional lives of high-achieving students. Procedures: This phenomenological study (Moustakas, 1994) explored the lived experiences of 24 high school graduates who took four or more AP courses during at least one academic year. A single overarching question guided this study: How did taking four or more AP courses during an academic year impact a high school student's life? Using purposeful convenience sampling and snowball sampling (Creswell, 2007; Bogdan & Biklen, 2007), data were collected from participants through interviews, detailed field notes, written reflections, follow-up focus groups, and reflexive journaling. Data analysis involved initial coding, recoding, and pruning to derive the essences of the lived experiences. Data were verified through triangulation, thick description, field notes and observations, reflexive journaling, and member checking. Written findings reflect the phenomenological tradition of narrative description to capture participants' lived experiences. Findings: Data analysis revealed themes that capture the essence of participants' lived experiences while taking four or more AP courses: (a) motivations, (b) stress, (c) extracurricular activities, (d) sacrifices attributed to course load, (e) family, friends, and like-minded classmates, (f) coping strategies, (g) balance, and (h) successes and regrets. The participants' stories reflected the situational uniqueness of each AP student. Conclusions: Parental support, teacher support, ethnicity as well as friendships and social connections shaped participants' experiences. The power of social media also became evident as participants communicated with the researcher and each other throughout this study. High-achieving students who pursue rigorous AP coursework can benefit from the lived experiences and perceptions of former students. Recommendations: High schools should provide more resources to high-achieving students who take rigorous AP course loads. Students may benefit ongoing mental health assessments to determine stress levels and coping abilities. Schools might offer seminars and workshops for students, parents, and school personnel in the demands of AP coursework, study skills, time management strategies, stress reduction techniques, healthy habits, and local resources. Schools should also facilitate connections among AP students, both current and former. School personnel may wish to ensure the fidelity of AP curriculum in providing challenging learning experiences rather than more work. [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://www.proquest.com/en-US/products/dissertations/individuals.shtml.]