In this study, I conducted class action-training-research on the use of coordination training in physical education classes at Japanese junior high schools. Coordination training was conducted with 177 boy and girl students for 3 hours on physical fitness. This study aimed to verify the effects of the training on students' enjoyment of exercise and sense of physical competence. Questionnaires were introduced at the beginning of the first period and the end of the third period to compare scores on physical competence (perceived physical competence, feeling of control, peer and teacher acceptance) and diagnostic and integrative class evaluations (affective goals) were conducted before and after the unit, overall and by gender. The results showed that the overall scores were higher for perceived physical competence (p<.001), overall physical competence (p<.001), and peer and teacher acceptance (p<.05). In the girls' class, the scores were higher for perceived physical competence (p<.01), peer and teacher acceptance (p<.05), and overall physical competence (p<.05). In the boys’' class, the scores were higher for perceived physical competence (p<. 01), feeling of control (p<.01), overall physical competence (p<.01), and affective goals (p<.01). In all cases, the scores were higher after the unit. This suggests that the introduction of coordination training in physical education classes at junior high schools is an effective means of making students experience the enjoyment of exercise and helping them develop a physical competence