I once shared a room with a teacher that had a terrible time with discipline. As I was in my first or second year as a teacher myself, I was not much better at it, and my presence in the back corner of the room grading papers, etc. did not make much of a difference in student behavior. One day she came in with a bell. She had seen another teacher use it to get her students' attention and it worked like magic! She was desperate for similar magic in her room so she tried it--and it worked!--the first time she used it, but never again. Obviously, if her students were disinclined to listen to her, they were not going to listen to her ringing a bell. It worked for the other teacher because she was a teacher who kids listened to, the bell was simply a device to save her voice.
The lesson that I took away from that is to be skeptical of "bells and whistles." There are many salespeople, reformers and officials that will try to convince you that they have the thing, the product, the program, that will make all the difference. However, the truth is that a solid teacher can make any program or device or even an actual bell or whistle look like magic-- and there will be times that even those teachers will swear by it! But in the end there will never be a substitute for solid teaching skills.
Practicing improv can improve teaching. First and foremost it can create better communicators. Improvisors listen with a willingness (even an eagerness) to change. They tap into non-verbal communication, showing interest, or seriousness or excitement, not just telling. Next, improvisors become "expert status players," smoothly and quickly adjusting the level of authority or presence within the room to match the needs of the activity or situation in the moment. This makes them more comfortable letting kids take the lead in a lesson, because they know they can establish control in an instant if things go wrong. Lastly, they see students as fellow players in the game, not just observers--engaging them in new and exciting ways, and enabling them to take an active role in how the class proceeds.
It is important to see the games and activities that are the core of any improv book or workshop (and this website) as a means to that end, and not just some sort of magic tool that will solve all of our classroom problems. If a teacher does not embrace the values and skills that make improv work, then improv activities will not work. Improv games are not a magic bell that instantly gets kids to have fun and be creative. The games are to help teachers practice and share the skills and values that are so important to teaching in today's world. The magic of these games lies in the teacher's willingness to play.