Using 25 newly purchased ukuleles in various colors, kindergarteners at Millwood Kindergarten Center in West Valley started playing the small instruments this spring as part of regular music sessions. The site has 231 students, ages 5 to 6. Two to three during the week, each of its classes has 30-minute music instruction. Earlier in the school year, they learn basics like singing, counting in rhythm, and playing simple instruments, before introduction of the ukulele.