We made ellipses that flashed black and white on the inside, changed the background's color and made the stroke weight increase with every other click, when they were pressed.
Here's our collaborated project:
After we collaborated, I played even more with our project and made it sound interactive. Now, the buttons change in diameter to the amplitude of the music.
Clicking on the buttons continued to change the background to different colors. The diameter continued to interact with the amplitude of the music, and you could also draw dots all over the screen. [Try it]
And after a while, I just continued to add and take out different elements to make it more or less sonically interactive.