One challenge with education is that expertise is so widespread. I've found that most people who have attended school act as though this experience qualifies them to be an expert in education. This is especially true of professors, who have attended school for 20 years or more. This attitude reifies existing educational practices andmakes educational change much more difficult than it might otherwise be.
These alternate conceptions begin very early. One study invited elementary school children to use a free period to teach themselves something. What did the students do? They gave themselves assignments and wanted to test or quiz themselves. A number of studies have demonstrated that people are most likely to teach a subject the way they themselves were taught.
A study of novice students of education found that conceptions about teaching were focused very tightly on classroom performance: the "stand and deliver" model of education.
I have often asked audiences to reflect on what other activities are "like" teaching to try to get people to reflect on the metaphors and mental models they use to organize the idea of teaching for themselves. The most common responses tend to be comedian, performer, or commentator.
I ask people to consider "an artist giving a show" as a potential model for teaching. Like a painter showing a series of paintings, most of the work is behind the scenes, as the teacher creates a series of experiences and activities for students to engage in. The show represents the audience's experiences with the paintings. The artist is often there, to ask probing questions or to encourage people to consider something they hadn't thought of, but the emphasis is clearly different. Note that I'm not saying that the two are identical, but that hits closer to me that the others, which seem like the primary interaction is centered around and through the teacher.