The present study, a case study of physical education class in an elementary school, focused on hesitations of pupils, who experience rhythm play for the first time, clarifying learning contents and implementing three case lessons based on systematic learning to remove the hesitation. This study explains the changes in pupils' movements and expressions through the lesson aiming to relive the hesitations. During the lesson, the pupils acquired movements that they had experiences of, made their understandings of good movement, and utilized and further explored the movement. The lesson removed pupils' hesitations one after another through a systematic learning, which encouraged the pupils to arrange movements and managed to express their feeling/rhythm. Further investigations are expected to organize systematic learning contents about what to teach and what pupils should think and express within eight years from first to eighth year.