Hi, Mrs. Duck-
I use a modified version of the Kodaly method all the time with ages 5-11. It works well to develop what I call "musical ears" and is developmentally sequenced (sorry for the teacher-speak) in a step-by-step manner. It teaches musical literacy slowly and gradually, with appealing songs and games. I haven't tried it with children younger than our kindergarten, and am really only now, 2/3 through the year, beginning to apply real Kodaly principals to the youngest children. But it can be done, I think. There are 2 classic books, "The Kodaly Method" and "The Kodaly Context" (dunno the authors) which lay out the whole program with song examples, lesson plans, and so forth. It's worth trying on the wee ones! Let us know how it goes!