To make sure we are all on the same code today, I had a go my self at getting two mBots to sing in harmony.
This week, I sent the code to the students in this format. Link to file here.
They then had to work as a team to work out who was going to be main melody and who was going to be harmony.
So after adding some suitable coloured lighting effects and then putting the code on extra mBots so they could place them in a Christmas Tree pattern, here is the finished choir.