http://knowledge.wharton.upenn.edu/article.cfm?articleid=2032

The Objective of Education Is Learning, Not Teaching

Traditional education focuses on teaching, not learning. It incorrectly assumes that for every ounce of teaching there is an ounce of learning by those who are taught. However, most of what we learn before, during, and after attending schools is learned without its being taught to us. A child learns such fundamental things as how to walk, talk, eat, dress, and so on without being taught these things. Adults learn most of what they use at work or at leisure while at work or leisure. Most of what is taught in classroom settings is forgotten, and much or what is remembered is irrelevant.

In most schools, memorization is mistaken for learning. Most of what is remembered is remembered only for a short time, but then is quickly forgotten.

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It is apparent to those who have taught that teaching is a better way to learn than being taught. Teaching enables the teacher to discover what one thinks about the subject being taught. Schools are upside down: Students should be teaching...

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There are many different ways of learning; teaching is only one of them. We learn a great deal on our own, in independent study or play. We learn a great deal interacting with others informally -- sharing what we are learning with others and vice versa. We learn a great deal by doing, through trial and error. Long before there were schools as we know them, there was apprenticeship -- learning how to do something by trying it under the guidance of one who knows how. For example, one can learn more architecture by having to design and build one's own house than by taking any number of courses on the subject. When physicians are asked whether they learned more in classes or during their internship, without exception they answer, "Internship."

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I can't very well explain to you how Newton accounted for planetary motion if I haven't boned up on my Newtonian mechanics first. This is a problem we all face all the time, when we are expected to explain something. (Wife asks, "How do we get to Valley Forge from home?" And husband, who does not want to admit he has no idea at all, excuses himself to go to the bathroom; he quickly Googles Mapquest to find out.) This is one sense in which the one who explains learns the most, because the person to whom the explanation is made can afford to forget the explanation promptly in most cases; but the explainers will find it sticking in their minds a lot longer, because they struggled to gain an understanding in the first place in a form clear enough to explain.

The second aspect of explaining something that leaves the explainer more enriched, and with a much deeper understanding of the subject, is this: To satisfy the person being addressed, to the point where that person can nod his head and say, "Ah, yes, now I understand!" explainers must not only get the matter to fit comfortably into their own worldview, into their own personal frame of reference for understanding the world around them, they also have to figure out how to link their frame of reference to the worldview of the person receiving the explanation, so that the explanation can make sense to that person, too. This involves an intense effort on the part of the explainer to get into the other person's mind, so to speak, and that exercise is at the heart of learning in general. For, by practicing repeatedly how to create links between my mind and another's, I am reaching the very core of the art of learning from the ambient culture. Without that skill, I can only learn from direct experience; with that skill, I can learn from the experience of the whole world. Thus, whenever I struggle to explain something to someone else, and succeed in doing so, I am advancing my ability to learn from others, too.