This research aims at understanding in depth what the motivation or reasons were for the elementary school girl students to have actively participated in school sports club league, why students avoided it, and what they felt in the process of preparation. Six students in S elementary school located in D metropolitan city, who had joined the school sports club league in 2015, were selected as the research subjects, and the preparation scenes for the school sports club league was observed vividly by this researcher in person from April, 2015 to July, 2015. In addition, efforts were made to understand the subjects by referring to in-depth interview data, journals and the researcher's daily records of the filed, and the following results were attained through an analysis method from various angles, examination among members, and discussion among coworkers for the fidelity of the data. First, the motivations in the elementary school girl students' participation in school sports club league were turned out to be ʻthe field to form companionshipʼ, and ʻrewards.ʼ Second, the reason why the elementary school girl students avoided the school sports club league was found to be ʻworry and burden.ʼ Third, it has been turned out that during the participation process in the school sports club league, the elementary school girl students had some ʻopinions about the teachersʼ, ʻsense of achievementʼ, and ʻregrets.ʼ