How I Use It
I have used this program to teach math to 3rd graders: whole, 1/2, 1/4 and 1/8. I have some music in my background and I'm sure that helped me plan how to teach them, but once the children are taught the symbols that represent 1, 1/2, 1/4 and 1/8, and if it is kept in 4/4 time, they can build models with these units and by trial and error come up with interesting melodies.
I love it, but it may require some musical background on the part of the teacher to be able to implement it. One has to place the notes rather precisely and this may be difficult for children who lack patience. The interface is fairly intuitive, but I would say it takes at least 15 minutes to learn well enough to use to teach to young children.