The purpose of this study is to overview how physical education teachers at junior high schools can acquire “lesson planning ability” through participation in workshoptype (WS-type) school training. According to this case study, the findings can be summarized in three points: (1) physical education teachers improved in their “lesson planning ability” through preparation of a guidance plan in WS-type school training and in exchange with others. (2) WS-type school training functions as a place to learn theory, a place to output, a place to deepen exchange between teachers, a place to share knowledge, and a place to contribute to the training of teachers’ “lesson planning abilities.” (3) Cooperation with schools, educational committees, and universities is indispensable in order to carry out “subjective, cooperative, and active” WS-type in school training.