I do a project in college for kids. I have 4 plates which lay on the ground and the kids can jump from plate to plate to play melodies or rhythms. It's more like a proof of concept, if it makes fun and works for kids. I saw the piezo drum example sketch and get one plate to work with that sketch. Now I want to connect 4 plates playing 4 different midi notes. I thought that should not be that difficult but because I am total beginner I was not able to get it running. I thought about to use the array command but I am not really sure where and how to put it in. Could someone of you help me with a solution?

Sorry for any mistakes, I am not a native speaker.