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Results from Learning Sciences
By Ken Bain
1. Knowledge is Constructed
People learn by constructing their knowledge. Learning is the dynamic process of modifying our memories. Rather than thinking of memory as a warehouse of stored information, it is more accurate to think of memory as both a processing center and a storage center. Roger Schank, director of the Institute for the Learning Sciences at Northwestern, explains it this way: "Learning depends upon inputs. . . .The role of memory is the interpretation and the placement of those inputs. Memory must decide what's worth keeping by determining what the meaning of an input is and where it fits in relation to previous knowledge it has already stored. That is, the very knowledge that was stored away in memory [helps] to process new situations. . . ." Human beings begin constructing mental models of reality early in life, and by the time students reach college, they have thousands of deeply rooted models of reality, or what some learning theorists call schema. When they encounter something new, they try to match it or compare it with something that is already in their memory. Schank puts it this way: "When you learn new things, as you are all the time, the new knowledge must perturb the system in order to find its place in memory in relation to what is already there. Does it amplify old knowledge, or contradict it? The mind needs to resolve these questions as new knowledge appears, getting reminded of what it already knows or believes each time some new experience occurs. This process of reminding and comparison is a critical part of learning. Thinking depends upon our ability to generalize and merge new knowledge with older memories. Teaching must make use of this natural process or fail miserably in getting anyone to ever remember anything at all that has been taught." We do not transfer knowledge; rather we can communicate information (including information about ideas), arrange experiences for our students, and bombard their senses, but they must construct their comprehension and develop the ability to apply, analyze, synthesize and evaluate. Because students bring models of knowledge with them to our classes--preconceptions that have a profound influence on what they think they learn and how they react to what we tell them--what we say does not travel as a seamless entity into their brains. Students wrap what they hear around a mental model and it often has more influence than what they hear or read. As Mark Twain said, "It's not what you don't know that hurts you. It's what you know that ain't so!"
2 Fundamental Concepts Change Slowly
People are usually quite reluctant and slow to change their mental models in any fundamental way. They tend to do so only when their mental models will not help them explain something about which they care. Schank calls these situations "expectation failures." In his view, "when your expectations fail, you know that your theory. . . needs to be adapted. If your theory was perfect, after all, you would never have generated an incorrect expectation. When faced with expectation failures, we, logically enough, attempt to repair the structure that generated the expectation. But this is not simple to do. Since many different memory structures provide expectations at any one time, how do you know which of those structures needs work?" You know by trying to explain the failure to yourself or someone else. When you reach a tentative explanation, you index it in your memory in the appropriate "knowledge structure." When several failures have the same explanation and point to the same knowledge structure, you simply change that knowledge structure. If we simply tell students the right answers, often they will not change their mental models. Instead we need to create safe environments for students to experience the failure of their mental models. Because we must place students in situations where their mental models will not work, we must understand their mental models by listening to their conceptions before we challenge them. Rather than telling students they are wrong, we must ask questions to help them see their own mistakes.
3. Questions make the difference
We construct knowledge by asking questions. Questions serve several functions: they point to holes in our knowledge and memory structures and are critical for indexing the information that we attain when we develop an answer for that question. Some cognitive scientists think that questions are so important that the information and skills we learn in developing an answer cannot be learned until the right question has been asked, because without having asked the question, memory will not know where to index the answer. For example, when a student faces an expectation failure, she will begin to ask herself questions to explain why her theory was incorrect. Again from Schank: Such failures force us to ask ourselves questions like 'What caused the failure?' and 'How can I prevent the failure from occurring again?' But expectation failures are not the only times when we sit back and ask ourselves questions. Sometimes, we are faced with a new problem and need to develop a new plan. In such cases, we might proceed by asking ourselves 'What old problems is this new problem like?' or 'How can I break down this problem into simpler problems?' Other times, we puzzle over our experiences, asking questions such as, 'What would have happened if I had behaved differently?' and 'Why did X act as he did?'" The more questions we ask, the more ways we can index a thought in memory. Better indexing produces greater flexibility, easier recall, and richer understanding. If we ask many questions, we build detailed indices that enable us to use knowledge gained in one context in other situations.
4. Caring makes the difference
People learn best when they adopt a goal that they care about attaining. In the natural learning process they will then generate questions and develop answers to those questions. If they don't care, they will not try to reconcile, explain, modify, integrate new knowledge with old. They will not try to construct new mental models of reality. They may remember information for a short period (long enough to take the test), but only when their memory generates questions, will it be prepared to change knowledge structures because only then does it know where to place an answer. If it is not seeking an answer to anything, it will pay little attention to random information. Schank notes an important implication for this concept: "The transfer model proposes that one learns effectively by being told. No doubt learning occurs in this way sometimes. We can learn by being told. However, we can only learn in this way when we care about, and are ready to hear, whatever it is we are being asked to learn. The real trick to teaching, in fact, is to bring the student to the point where he is ready to hear something. The transfer model, teachers talking at students, is not particularly effective at getting students to that point."
By Ken Bain