First this study aims to clarify how elementary school teachers of B Prefecture informed their learning outcomes by in-service training of physical activities to their school colleagues. Secondary this study aims to clarify how in-service training of physical activities at D Elementary School in C City influenced improving school teachers' teaching in physical education. The results are summarized as following points. 1. Elementary school teachers of B Prefecture informed their learning outcomes to their school colleagues through 'in-service training meetings within their schools' or 'their daily job'. 2. D Elementary School Teachers have taught new teaching materials as learning outcomes from ‘in-service training meetings of physical activities'. 3. Teacher X and Teacher Y learned teaching method and subject knowledge of physical education by team teaching experiences with PE coordinators as 'their daily job'. Teacher L learned the way of making unit plan, modification of activities and management of his class from his elder colleague K by dialogues about teaching in physical education as 'their daily job'. 4. It seems that it is important we make mentors' daily supports to mentees between PE coordinators and other school teachers.