1. "Yes, and..."
"Yes, and..." is the most important concept in improv theater. It would be impossible without it. It is the simple idea that when working in a group, whatever the idea is, you should enthusiastically accept that idea. You can do this by saying "yes" directly, or by simply accepting the offer being made fully. This is not enough, however, step two is to say "and" then add to the idea being offered. When we are working in groups, ideas really take off when group members enthusiastically accept an idea and add to it so that by the end it is hard to tell what parts of the final project came from who. Remember, "Yes, and..." is not a script, it's an attitude, a way of approaching a problem. It is also can be used in class as a verb--"Yes, and that idea!" "Pick two items from that brainstorm and yes, and them--see what comes up..."
2. Point of Focus
We should never be on stage without something to do, and as teachers we should never put students on stage without a task. The real fear in public speaking or acting in front of an audience is the fear of not having anything to do. The term "Point of Focus" was coined by Viola Spolin. The notion was that every actor needs to be told or have in mind a point of focus while they are on stage, and we as audience members and directors can evaluate the performance based on whether or not they achieved that focus. As actors, we should be always asking ourselves if we are achieving our focus.
Never go half way. "Go big or go home." The worst thing actors can do on stage is to be tentative. This is probably the most common "side coaching" comment. Encourage students to go into activities with confidence and energy, and do them fully. If they are going to fail, fail big and with gusto!
We are always afraid to just let the first thing that comes to us out. We want to be funny, smart, clever or conversely we want to hide who we really are or just not be noticed at all. The Ancient Greeks had the idea that creative acts did not come from us, but from the "muses." This freed them from this problem. If the idea was bad, or disgusting or whatever, it was not the artist, it was the muse. Keith Johnstone suggested that the way to be truly unique is to be ordinary. Your ordinary is different than other people's ordinary and they will find it very unique, but at the same time simple--"Why couldn't I come up with that?!" So stop thinking about it and let yourself be surprised at what comes out!
Building trust is the key component to any classroom environment. Students need to trust you and they need to trust each other. Improv games are great at giving students practice at this. They give them the opportunity to step up and save a fellow student who has run out of ideas. They give kids the feeling that they should not be worried about "bad" ideas, because whatever they say they will be supported. The more they can practice this, the more they will take risks, and the more they will learn.
In an operating room or a cockpit, when lives are on the line, failure cannot be an option. But in a classroom, any classroom, failure is an opportunity to learn. To fail at a task needs to be seen as an opportunity to try again, take another turn. To fail does not make you a failure. It makes you more experienced. Experience students will need to become more resilient... Experience that students will need if they become surgeons or pilots.