This study aimed to examine movement fluctuations through a quantitative analysis of the musical expression of 3-year-old children in their daily lives and with respect to the practical process of the MEB program, which utilizes the MTw system. The 3-year-old children included among the total number of participating children (n=115) attended to two nursery schools, which adopted different childcare forms. It was found that the movement elements in musical expression of the children were observed more frequently at U nursery school, where the children frequently engaged in make-believe plays and dramatizations, than at K nursery school. With the MEB program, the moving average of acceleration fluctuated more frequently and the vertical amplitude became intense. As a result of Fourier transform, periodograms of the U nursery schoolchildren included wave patterns that showed vertical undulations and declining pattern. Periodicity was observed in the fluctuation of the moving average of acceleration. With respect to musical expression, the moving average of acceleration in 2014 with the MEB program was greater than that in 2013, which was before the MEB program was implemented. This result indicates a relationship between movement elements and the recognition of musical elements by the children. The data from K nursery schoolchildren showed a clearer periodicity in the moving average of acceleration than with the U nursery schoolchildren. A clear periodicity indicates that the child feels a regularity of a beat and the rhythm and moves. Some characteristics concerning musical expression could be extracted from movement analysis based on differences in the two childcare forms.