I am not looking for a job opportunity, but good luck with your extension to Japan.
The children I have worked with showed a significant difference in their behaviors depending on music they listened to. I used music as one of my teaching tools when I worked with toddlers. Bach, Mozart were played before nap time; Miles Davis, Theronious Monk, John Coltrane were played during activities and meal time, never played Barney or Wiggles for the kids even though they were popular and heard on TV all the time.