What is the added value of a good physics teacher?

Our incoming headmaster addressed the faculty last week.  I was pleased and impressed with the discussion he raised about our fundamental reason for employment.  Regular readers can probably infer that I'm generally UNimpressed by eduspeak, mission statements, anything suggesting that we should go forward into the future, twirling towards freedom.  Nevertheless, the headmaster raised an excellent meta-question, one worth pondering.

So much teaching is done the way the teachers themselves were (or wish they had been) taught.  The headmaster noted that in our day* information was scarce, so we were necessarily taught to spongily absorb facts and knowledge.  Today, information is over-abundant.  Thus, our teaching should change focus, toward "constructing stories to make sense of plentiful information."  He asks, as I paraphrase: What do our students most need from us given their time and place?  

* "Our" day... that's a scary thought: the new headmaster's kids are younger than mine.  Crap, I'm old.

This is not intended as a physics-specific question.  I know the physics answer: I teach all my students the "big three" physics skills, working through enough topics with those skills that they can perform on externally-validated AP or Regents-style exams.  That's not the issue.  The headmaster is asking a more general question.  

With the easy availability of textbooks, Khan Academy, and Webassign, a physics teacher could nearly automate his class.  In my own mind, a teacher running such a class would be criminally defrauding his school of his salary.  That's not teaching.  But, the headmaster asks, if that's not teaching, what is?  What added value can I personally provide, over and above the myriad of available resources, such that it's worth it for parents to pay me for my services?

I've got two answers.

One: I can teach my students about experimentation, and how experimentation relates to pencil-and-paper problem solving.  There's no video, simulation, or textbook description in the universe that provides the same hands-on experience with equipment that the laboratory portion of a physics course can.  By the end of the course, my students are well used to thinking "how could I check this answer with an experiment."  They understand that taking three data points and debating the pattern they form is crap science; they know how to plot data on a graph, and how to use that graph as evidence for the validity (or lack thereof) of theory.  

Two: I can teach my students to communicate their understanding of a quantitative subject.  My students are good, smart boys who are used to getting answers right in school.  They enter my class with the idea that their job is to understand the subject.  I ask them to do more -- I ask them to communicate their understanding via words, diagrams, equations, and numbers.  They learn that getting an answer is insufficient; even knowing how to get the answer is insufficient.  They must be able to explain in thorough detail the reasoning behind their answer, such that another person at the same level of physics can easily follow and understand their approach.  The English department doesn't accept a one-sentence essay along with a plea that "Come on, you know what I mean;" neither do I accept two lines of algebra as justification for an answer, even if the student claims to know in his mind how to do the problem.

The teaching of experimentation and scientific communication are both time consuming, intellectually intensive processes.  My students don't usually recognize the necessity of developing experimental and communication skills; they think that they already know about experiments from middle school, and they think that their communicative ability is already perfectly good because they can often get answers right.  So my job begins with convincing the class that they need to develop these skills in the first place.  Then I must ride herd all year, never allowing a substandard experimental graph or half-arsed justification to slip through unchecked.  When a student is honestly stumped as to how to improve his experiment or his justification, I have to find a way to patiently explain, to help him improve without merely doing the heavy thinking for him.

These skills of experimentation and quantitative communication transfer to most disciplines beyond physics.  Every science, every social "science", journalism, politics, business, sports, virtually everything my students might eventually do will be helped by their ability to collect data, evaluate data, and communicate an understanding of the meaning of that data.  And that's why physics teachers who help their students develop these skills should be in high demand.