Abstract
This study investigates the improvement of an orientation course for technical intern trainees in Japan through action research. The course, taught by seven graduate student instructors, revealed challenges for inexperienced teachers who did not fully follow the course design. Key issues identified include insufficient understanding of learners' profiles, lack of concrete lesson images, and ambiguity in overall course goals. These role perceptions and miscommunications hindered collaborative course management. The findings suggest that sharing a clear and concrete course vision is essential to help inexperienced teachers effectively participate in team teaching roles, enhancing the overall course execution and management.
