I subbed today for a high school social studies teacher, one whom I've subbed for many times.
I ended up having to review game, which was sort of a combination of bingo and connect-four. I discovered that it IS, in fact, a good idea to carry a bag of several multi-sided dice with you wherever you go. You never know when you'll need to randomly generate numbers, or even letter-number combinations.
Also, when subbing, it is absolutely essential that you have your own little bottle of hand sanitizer with you wherever you go. Just trust me on this.