Abstract
This paper reports on an action research study focused on the development and implementation of an annual syllabus in a community-based Japanese language program organized by City A. Using a cyclical action research process—planning, action, observation, and reflection—a team of instructors collaboratively designed and revised the syllabus over three cycles in 2023. The findings indicate that a structured syllabus enhances pedagogical coherence, learner autonomy, and instructional alignment. The study highlights how action research can support sustainable curriculum innovation in non-formal language education, particularly in community-based contexts that utilize team-teaching approaches.