I've been teaching at the college level for almost nine years. This is the longest I've held down any kind of job. Among all of the jobs that I've had, most of which are in retail, this is by far the job that I enjoy the most. I feel a bit anxious as it may come to an end as I complete graduate school. Getting a job as a philosophy professor is not all that different from trying to get drafted to a professional sports team as a collegiate athlete.
Anyways, I have a lot of interest in teaching, and have put some amount of thought into it. I figure I'd lay out some of thoughts here in the form of an analysis.
So what exactly is teaching? Let's start at the most general level. First, there is the descriptive/normative distinction. What is it that teachers actually do, and what should they do? I'll start with the first.
Anytime you interact with someone, and the goal of that interaction is to impart knowledge on that individual, you are teaching. Knowledge in this case could be a "knowing that" kind of knowledge, in which you are conveying some amount of information, or it could be a "knowing how" kind of knowledge, where you are trying to impart some sort of skill or ability.
The "knowing that" and "knowing how" distinction is important, as we shall see below.
The rough definition given above should be good enough for this little essay. There might be some borderline cases that don't fit the definition, but I don't think we should be worried about them.
If that is what teaching is. Then what should good teaching look like? This depends on the context, as teaching occurs in a variety of situations.
The context that is relevant here is institutionalized teaching, i.e. the kind of teaching that you see in elementary, middle, high schools, and in college. What are teachers supposed to do in these contexts. What are they supposed to convey?
The conventional thought regarding institutionalized teaching is that it's all about the conveyance of "knowing that" knowledge. Teachers are tasked with transferring information. It doesn't take long to realize that this view is incomplete. It is true that part of what teachers do is transfer a body of information, but surely teaching from kindergarten through college is more than that.
Let's look at it from the other end. What is the point of going to school as a student? What is the goal or purpose? The answer is not so clear cut, as there are probably several goals. Two goals that are prominent in a liberal democratic society like the United States are political and economic in nature. The political goal of education is to produce effective participants in the democratic process. The democratic goal of education is to produce individuals who effectively contribute to a more or less capitalist economic system.
What does it mean to be an effective participant in the democratic process? It probably means being able to make informed decisions about public policies and, in the case of our government, to be able to choose an individual that best represents those informed decisions in local, state, or federal government.
Capitalist systems are usually about growth. So, to effectively contribute to a capitalist system is to contribute to the system's growth. How society grows economically will be a function of various factors, which can include manufacturing, information, service, finance, etc.
So, given that those are the goals of an American student, education is recognized as a means to that end. Thus, what teaching is supposed to be at the institutional level is the imparting of knowledge (both knowing that and knowing how) required for the student to meet both goals.
Of course this is still an incomplete picture of what teaching in a school setting is all about, but it's a start.