The purpose of this study is to investigate the effectiveness of family studies incorporating role-playing based on Kohei Matsumura's interpersonal relationship theory, using a multi-layered baseline design. It was carried out with junior high school teachers with no experience in role-playing as instructors.

  The study did not detect significant differences in educational effects between role-playing and whole-class lessons. However, through family studies, there was a positive shift in junior high school students' self-assessment values regarding awareness (interest, acceptance, understanding) of parents and families, and action aimed at improving parent-child and family relationships. This indicates an overall educational effect of family studies including both role-playing and whole-class lessons.

  It became clear that family studies, including role-playing based on human relations studies, can influence relationships between students and their parents or families, even when taught by home economics teachers without prior experience, following training sessions.