For some sub gigs, I'm given a veritable punch-list of things to do with students. I appreciate this sometimes: it ensures that we won't be at a loss for what to do. At times it is hard to know how serious the teacher is about the list. Do I have so many things on the list because the teacher really thinks they all ought to be done or is it a kind of "mercy" for the sub to have more than can be accomplished so that the kids will stay busy? I generally take the stance that the teacher has in mind the latter and that getting at least some of these things done is the goal with the perhaps unstated goal being, teach them something.
Flexibility is important.
"What's the most important thing (in life)?"
Micro-Case Study #1. I was "thrown-in" to sub for a sub for the first period of a U.S. Government class. After a sentence stem writing exercise, the question of Donald Trump's "suitability" for running for President came up. This led rather directly to questions about how to sort out the best person for the job. Ought it to be something to be sorted out by the system or settled a priori? Good conversation. Essential question: who decides? Pointed to the need for philosophy, for sure.
Micro-Case Study #2. Same day: three sections of World History. Activity: jigsaw elements of French Revolution and the Terror (nine groups). I'm in a bit of logistical hell, here: how to keep kids on task? Well, a struggle but not a failure. The essential question: How did those high ideals of the Enlightenment (Liberty, Equality, Fraternity) turn to the guillotine and buckets of blood?
Questions of meaning are always there.