Google Code-in

Make a software (piano-type) keyboard where notes can be selected, performed, and generated into pitch blocks.

Something like this would be a nice start: http://www.piano-keyboard-guide.com/wp-content/uploads/2015/05/piano-keyboard-diagram.gif

This is a working example (but only with a very small keyboard) http://makeymakey.com/piano/

Then, make the keyboard scalable (more/less keys)

fun, fun, FUN!