You can code whatever note you want and I chose from left to right the piano notes G4, A4, A#4 and C5. It's an easy project using the arduino program and it's pretty self-explanatory: you press one of the first four buttons and the buzzer will play a note. I immediately knew what I and my partner were going to do. When I was looking at random projects I saw a mini-piano arduino instructable and. I wanted to do something not too hard, but also something that's in my interest. So first off, I had to make an electric device for a school project.