Young people in vulnerable situations tend to have more difficulties realizing successful formal education trajectories. It is extremely important to conduct studies that explore the key dimensions that can help young people overcome the conditioning of vulnerable situations, assisting in the achievement of academic success. According to the existing literature, one of these key dimensions is psychosocial well-being. Thus, this qualitative research aims to identify and analyze psychosocial factors that favor successful school pathways among young people in vulnerable situations. Through a case study approach, 12 in-depth interviews were carried out with 12 young Spanish people who not only have a vulnerable background but also successful formal education trajectories. The data were explored through qualitative content analysis—NVivo11. The results revealed that young people generally associate their successful educational trajectory with the positive impact of psychosocial factors, such as the following: positive caregivers’ valuation of formal education and positive school experiences and support networks. Young people also point to many negative school experiences that have been overcome via positive attitudes and individual protective factors. The youngsters suggest changes in the educational system and teachers’ skills in order to improve the levels of psychosocial support in formal education contexts. The study’s implications and limitations and recommendations for future research are discussed.