Use Tone Matrix to generate music by clicking squares on a grid.
Screen capture from Tone Matrix.
Another good music app comes from Incredibox:
Created on Incredibox.
Citing this post: Urbano, L., 2013. Music of the Squares, Retrieved April 27th, 2017, from Montessori Muddle: http://MontessoriMuddle.org/ .
Attribution (Curator's Code ): Via: ᔥ Montessori Muddle; Hat tip: ↬ Montessori Muddle.