A few years ago I did a stint as an instructor at a large state school teaching, among other things, business calculus. The sections for that course tended to be good-sized, usually running from fifty to one fifty. At one time, I probably would have found the experience a bit intimidating but I was just coming off a couple of years as a TA for a professor who routinely taught sections of more than three hundred so I considered myself lucky to be able to make out individual faces.
With few exceptions, experienced teachers are comfortable addressing large groups and with very few exceptions, effective teachers are comfortable demanding the full attention of those group. Along with knowledge of the subject, strong communication skills, and commitment to the students, a "when I talk, you listen" attitude is a defining trait of an effective instructor.
That doesn't automatically translate to a room full of kids sitting quietly while the teacher drones on. Often the result is just the opposite. Teachers are more likely to have looser classes with more student participation if they feel in control. As a rule of thumb, you should never be more than ninety seconds away from having every student seated and reading quietly. For really good teachers, even the most adventurous lesson plans fall into that ninety second radius.
Put another way, it comes down to authority. A teacher's job is to teach, counsel and objectively evaluate his or her students. A sense of authority is an essential trait for all these tasks but it's an incredibly annoying one to find in a direct report.
Good principals (and I've met some excellent ones) are masters at the difficult art of managing managers. They can exercise their authority in a way that actually enhances the authority of those under them.
Even with the best administrators, however, there is always an element of tension and it only gets worse with less competent principals and superintendents. This is something to keep in mind when you hear about plans to improve education by giving principals more authority to get rid of bad teachers. Sometimes bad doesn't mean incompetent; it means inconvenient. (I don't have the book in front of me, but Diane Ravitch' Death and Life has some notable examples.)
Originally posted in West Coast Stat Views