Behaviorist B. F. Skinner was one of the pioneers of the idea that the human being is born with a tabula rasa (an empty brain), and throughoutthe course of our lives we learn how to do things. This goes for everything under the sun - starting from a baby who learns how to walk after repeatedly standing up and toppling over and going all theway to professionals in a variety of fields who acquire their skills by extensive studies, but mainly by trial and error. This is, of course, a very simple and basic way of summarizing the theory ofbehaviorism.
In relation to teaching he was even quoted saying that "teachers must learn how to teach ... they need only to be taught more effective ways of teaching." Some say that people are eitherborn teachers or not, speaking of this as a talent or vocation. Others, including Skinner, say that just like any other skill, teaching is something that one can acquire.
Regardless of how and bywhich process teachers become teachers, the most important thing is that they deliver their message to their students, and in order to do so there are various aspects which they have to keep in mind -aspects that often go beyond how well they know the subject that they are teaching!
What must be taken into consideration when going into a classroom?
Sometimes teachers go into class with theintention of teaching a particular grammar point, let's say the Present Simple. However, it is also important to take other things into consideration, such as the different skills that teacher wants orneeds to include; or the topic/s used in the lesson. However the most important part of the lesson is always the student. There are various aspects which must be considered and these include the age,linguistic ability as well as the nationality of each individual student in the class.
Whatever the subject that you might be teaching, your students are always the most important...