This study examines the impact of teachers’ participation in in-school training on their self-efficacy and emotional exhaustion. The training focused on social support and was conducted six times, incorporating both instrumental and emotional support. The changes in teachers were examined through open-ended questionnaires and semi-structured interviews from theoretical descriptions derived from SCAT analysis. The results revealed the following: First, training in understanding students that provided 30 minutes of social support had the potential to increase teachers’ self-efficacy and was an effective support measure for reducing feelings of emotional exhaustion. Second, increased opportunities for teachers to interact with each other led to the formation of relationships among them, and the daily social support provided to teachers increased the likelihood that they would be able to work with each other. Second, we inferred that increased opportunities for interaction lead to the formation of relationships among teachers, and increased provision of social support on a daily basis reduces the sense of emotional exhaustion by increasing psychological safety.