This study aims to understand the experiences of preschool teachers' outdoor education experiences in their curriculum after taking the Outdoor Education in Early Childhood Course. In this qualitative study, grounded theory was applied to analyzing data that were collected through an open-ended form and individual and focus group interviews. Results consisted of a main category, namely change in the quantity and content of outdoor education. According to the results, the teachers' experiences changed to increase and enrich OE. The study revealed that improving the quantity and content of outdoor education by teachers leads to improvement in three interrelated categories: change in pedagogical approach, personal development, and children's development. These categories are development in coping with obstacles, risky play approach, communication style with children, child-centered practices, self-efficacy, emotional self-regulation, motivation to teach, problem-solving skills, and holistic development of children. Furthermore, all these developments function as mutually reinforcing factors.