Sometimes it's just easier to go to school than write out sub plans, right? That is especially hard in the music room. First, it's hard to find a sub who will take a music job sometimes--they think if they are not musicians, they can't do it, or they are not comfortable singing, etc. When you do find a sub, you never know what their musical skills will be. After many years of teaching, I came up with a Sub Notebook that actually works great for me.
First, there are the usual schedules, who to ask for help, copy codes, etc. Then comes the special section. I have a master list called an "Emergency Sub Plan". For this page, I list games/activities that each grade level already knows how to play. They are favorites that the kids ask for again and again, so positive participation is almost a guarantee! I try to update the list at least once every six weeks, to keep current faves on the lists.