Since the enforcement of the Child Welfare Law in 1998, children’s self-reliance support facilities (CSSFs; facilities for children who have displayed or are at risk of displaying unlawful or problematic behavior) have been gradually opening Alternative Provision schools (henceforth, AP schools). However, teachers generally do not know that they could be assigned to an AP school and how work conditions are in such schools. Previous studies have focused on the educational approaches and teaching methods in AP and traditional elementary and junior high schools and the issues associated with the cooperation between welfare and educational facilities. However, they have not focused on the psychological processes of teachers working at AP schools. To motivate teachers who are concerned about working at AP schools and improve education in CSSFs, it is important to clarify how teachers interpret their experiences of working in AP schools. In this study, semi-structured interviews were conducted with teachers working at AP schools. Interpretative Phenomenological Analysis was used to explore the meaning they assign to their experiences working at AP schools. The results showed that the teachers experienced a “change in the causal attribution of problematic behaviors,” “shifted to a holistic educational policy,” and “reconsidered the nature of the teaching profession.” The results also suggested that “pity and compassion” and “pride as a teacher/adult” influenced these perceptions. Initially, the teachers did not think deeply about the “causes of the children’s behavioral problems” and attributed them to the children’s personal issues. However, through their experience of working in an AP school, they came to learn about the children’s backgrounds and began to reflect on the causes of their behavioral problems. They began to emphasize fostering the children’s basic social skills rather than strengthening their academic performance and started devising new activities during classes. They found it rewarding that, due to physical proximity in the peculiar environment of AP schools, they could build close relationships with the children. However, they also expressed concerns about overstepping their boundaries as teachers and becoming fatigued.