My family helped me put on a performance to demonstrate how the MIDI note and key-press velocity data from a MIDI piano keyboard can help create an interactive animation of falling leaves. I programmed this demo in JavaScript, the coding language of the Web. Each key press creates a leaf at a random position along the top edge of the screen. Simulated physics forces of gravity and wind move the leaves. A cosine curve gently rotates each leaf back and forth. The non-changing gradient sky background is drawn into a background canvas image layer so that the computer only needed to draw it once.
My daughter performs the Scale in C-Major.