The aim of this article is to discuss the requirement of the Swedish Educational Act that says that the activities of school and leisure-time centres should be based on (soft) science and proven experience. The discussion is carried out through illustrations from a collaborative action learning project that took place between researchers and leisure-time teachers with the overall aim to strengthen evidence-based knowledge about leisure-time teachers and to clarify their proven experience. The combination of pupils’ proven experiences and the leisure-time teachers’ reflective and researching approach proved to be the best route to follow in increasing the quality of the leisure-time centres. The leisure-time centres involved, to a greater extent than before the project, are now built upon a scientific approach as well as the proven experiences of both the pupils and the leisure-time teachers. The project underlines the well-known facts that developmental work needs stability and continuity to lay the foundation for sustainable change and that changes need to be a clear part of the schools’ development organization.