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Teach Talk

The Contribution of Constructivism

Lori Breslow

This is the second of three articles reporting on the latest developments in the research on learning. The first described work on the differences between expert and novice problem solvers. This second article will look at a theory of learning called "constructivism," and its implication for teaching strategies. Unless otherwise noted, information for this Teach Talk comes from "Meaningful Learning in Science: The Human Constructivist Perspective" (hereafter referred to as "Meaningful Learning") by Joseph Novak, Joel Mintzes, and James H. Wandersee. It appears as a chapter in Handbook of Academic Learning, Gary D. Phye, ed., Burlington, MA: Academic Press, Inc., 1977.

 

Albert Shanker, who for many years was president of the 940,000-member American Federation of Teachers, is reputed to have had a sign in his office that read, "I taught but the students didn't learn. Define 'taught' in that sentence."

That sign came to mind as I began to work on this Teach Talk. It is a gripe that runs the gamut from elementary school to college classrooms: Although the instructor did his/her best to teach the material, the students just didn't learn it. This refrain rears its head at MIT when faculty teaching sophomores complain they need to cover material supposedly taught in the freshman year. And it is heard when faculty teaching upper level subjects wonder what went on in sophomore courses because students don't know the fundamentals of the field.

Of course, the natural tendency is to blame someone for this problem, and more often than not, it is the students who take the brunt of the attack. But if you listen closely, there are also subtle implications that faculty may be doing something wrong as well (trying to cover too much content or not enough; emphasizing theory over application or vice versa). I believe, however, it is entirely possible everyone is doing his/her best in the classroom even though the results are disappointing. It is possible the students aren't slacking off, but working hard, and that faculty members are putting hours of preparation time into lectures, recitations, problem sets, and exams. Yet still the students aren't learning – or aren't retaining – the subject matter. The problem is, like any other skill, success in teaching can only go so far if it is not informed by knowledge of the theoretical underpinnings of the endeavor, a familiarity with best practices, and a willingness to use both.

Work in the learning sciences, fed, in part, by cognitive psychology, has reached a state of development so that it can tell us something about how to channel our efforts in teaching for best results. The human constructivist perspective – so-called because its fundamental assumption is that learners construct their own knowledge – is perhaps the most fruitful of this work. It is an attempt to unite the psychology of human learning with the epistemology of knowledge production ("Meaningful Learning," p. 418). At its core is the idea that for humans, learning is a process of "meaning making," which entails the acquisition of concepts [the authors define concepts as "the basic units of meaning, as perceived regularities in objects or events that are designated by a sign or symbol" ("Meaningful Learning," p. 419)], the modification of concepts, and an understanding of the relationships between concepts ("Meaningful Learning," p. 418). For students in the sciences and engineering, a central task of education is to "make meaning" about the natural world and how to modify it productively.

 

Meaningful Learning

The human constructivist perspective, which began as early as the 1950s, sprung from the work of developmental psychologists, particularly David Ausubel. Ausubel theorized that as the learner forged links between old and new knowledge, and committed that new structure into long-term memory, he/she was engaging in meaningful learning. Cognitive science has recognized that learners "see" patterns in objects and events based on prior knowledge; that "what you see depends on what you know (and vice versa)." ("Meaningful Learning, p. 420). This idea, which is commonplace in both epistemology and the philosophy of science, led Ausubel to formulate one of his most important ideas about teaching. "The most important single factor influencing learning is what the learner already knows," he wrote in Educational Psychology: A Cognitive View. "Ascertain this and teach him [sic] accordingly." ("Meaningful Learning," p. 406).

So began a profound shift in the educational community's understanding of how learning occurred. Prior to Ausubel's insight, it was assumed learning was a one-way process from teacher to learner. Ausubel inspired educational theorists to conceptualize learning as an interactional process in which the learner's prior knowledge played a crucial role. Rather than being a blank slate, the student enters the classroom with notions about the physical world that come from a variety of sources, including personal experience, direct observation, sensory awareness, peers, the mass media, and previous instruction. The problem is sometimes those ideas are incomplete, inconsistent with accepted scientific knowledge, and/or downright wrong. "At last count," write Mintzes, Wandersee, and Novak, "just under 3500 studies [over 25 years] had addressed issues related to students' alternative conceptions in science." ("Meaningful Learning," p. 408).

Research has further revealed that students' age, gender, ability, or ethnicity has no effect on whether or not students hold misconceptions. More importantly, this research has also shown that once taking hold "these ideas are often tenacious and resistant to extinction by conventional teaching strategies." ("Meaningful Learning," p. 410). For example, Diana Laurillard, in her book Rethinking University Teaching, describes investigations undertaken to reveal misconceptions about Newton's Third Law. Freshman physics students were asked to apply the Third Law by describing the forces on a box resting on a table. Many of the students' explanations reveal their misunderstanding or misapplications of the law. According to Laurillard, the causes of this problem include everything from the "everyday experience of force," which override an abstract principle one only reads about, to mistakes in the way textbooks present Newton's formulation. This latter problem Laurillard calls "pedagogenic error," which, she writes, is "comparable to iatrogenic disease." (p. 42).

Difficulties in learning the central tenets of science, constructivism holds, derive from students' inability to construct meaning about the phenomena and relationships science seeks to illuminate. This can be caused by the fact that, as discussed above the learner's prior knowledge is faulty. Another reason may be that the student or instructor may not be committed to the student engaging with the material in any kind of substantial way. (For a discussion of the instructor's role in discouraging "deep learning," see "When Students Learn," Teach Talk, October/November 1996, http://web.mit.edu/tll/published/teach_talk.htm). In that case, "new knowledge is incorporated in an arbitrary, verbatim fashion," which Ausubel called rote learning ("Meaningful Learning," p. 420). Although the physiological process of incorporating concepts into long-term memory is not completely understood, there is some evidence that the duration and use of knowledge stored in long-term memory depends on the structure of that knowledge. Thus, students who merely memorize – without the linking that accompanies meaningful learning – are more likely to lose that knowledge. This would account for the fact that students often report they have never seen some subject matter even though faculty know they presented it in class.

Researchers in the field also have begun to uncover the learning strategies used by students who do master the scientific disciplines successfully. They have begun to understand the underlying conceptual work that students need to do in order to learn meaningfully. "The most comprehensive claim," Mintzes, Wandersee, and Novak write, "is that successful science learners develop elaborate, strongly hierarchial, well-differentiated, and highly integrated frameworks of related concepts as they construct meaning." (Ausubel et al., Educational Psychology: A Cognitive View, 1978, as cited in "Meaningful Learning," p. 414). At the heart of scientific learning, these researchers maintain, is the ability to understand the relationships between higher and lower levels of abstraction, how concepts are alike or different from one another, how one concept can be replaced by or substituted for another. Frameworks can be built gradually with refinements made along the way (a process called "weak restructuring"), or they can be altered radically to accommodate new superordinate concepts ("strong" or "radical" restructuring) ("Meaningful Learning," p. 415). The authors report that science students who achieve a high level of proficiency will use both weak and strong restructuring, with strong restructuring more common in the early phase of learning, and weak restructuring more prevalent as the class goes on. In other words, students must navigate major conceptual hurdles as they are becoming familiar with a topic or a course, but once they have done so, then they can begin to "tweak" their understanding of how ideas fit together. The question this brings us to, then, is what can be done in the classroom to nurture this kind of successful learning.

 

Instructional Strategies and Techniques

Mintzes, Wandersee, and Novak hold that in order to learn meaningfully, students need to focus specifically on concepts, the patterns they make, and the relationships among them. They and their colleagues have developed a set of what they call meta-cognitive tools that can be used for this purpose. These techniques have been designed specifically to help students learn how to learn.

The basic tool in their arsenal is the concept map. A concept map is a diagram of a particular domain of knowledge that places the concepts and constructs (constructs are higher order concepts) that form that domain on branches arranged in a hierarchy. Lines that link concepts are labeled so as to explain the relationship between the two entities (see example). Advocates of concept mapping suggest they can be used both as a learning tool for students and as an aid to assessment for instructors. Similarly, concept maps can also be used to brainstorm complex projects by giving the student (or students in the case of a team project) a guide to how ideas and/or tasks will link together to produce required deliverables. Concept webs and concept circles diagrams are variations on the concept map.

Vee diagrams help "students see how science makes knowledge and value claims" ("Meaningful Learning," p. 432); in other words, they help students comprehend how scientists have come to know what they know. Invented by D. B. Gowin, a Cornell University philosopher, vee diagrams are, in some ways, a rough reconstruction of the development of a particular field or idea (see example). Vee diagrams can be used to help students understand how knowledge is generated in the laboratory or how to critically analyze a research report.

Research on the effectiveness of both concept mapping and vee diagrams is encouraging. Studies have found students who use these tools "understand relationships between theory and method, ideas and observations . . ."; score higher in exams that include novel problem-solving activities; and have "positive attitudes toward the subject they study . . . ." ("Meaningful Learning," p. 435).

It may be, however, that the demands of the curriculum in most MIT subjects will not allow for the time required in class to have students make concept maps, vee diagrams, or the like. But what instructors must make time for, is to explicitly explain the links and relationships among the ideas in the material they are presenting and to address the common misconceptions which students hold.

 

One Simple Tactic: Address Common Misconceptions

This last point is worth emphasizing. Much instructional time could be saved – not to mention confusion avoided – if instructors thought about the ways in which their students are likely to misunderstand or misconstrue the concepts with which they are presented. Laurillard cites research on teaching subtraction in elementary school that uncovered 89 ways the students were doing subtraction incorrectly. "But," she writes, "by going to a different level of description, at the level of understanding, [two other researchers] found just two ways of misconceptualising subtraction" (Rethinking University Teaching, p. 37). Although the example comes from the K-12 realm, the lesson derived from it is applicable in higher education as well. "If a student borrows across zero incorrectly," Laurillard continues, "we want to teach him not 'how to borrow across zero,' but what 'borrowing' means." (Rethinking University Teaching, p. 37). The 89 ways of doing subtraction incorrectly are examples of what Laurillard calls "buggy algorithms" (i.e., flawed procedures); the importance of buggy algorithms is that they reveal fundamental problems with the way in which students are thinking about the underlying concepts. The interesting finding from both Laurillard's freshman physics experiment and the subtraction study is that if the instructor looks further than the superficial mistakes, he/she is likely to find a relatively small number of conceptual misunderstandings at the base of those errors. And because these conceptual problems are relatively small in number, addressing them in class is not only entirely possible, but an efficient use of time. As Laurillard writes, "If you remediate one of the 89 wrong procedures, you have another 88 to contend with; but if you remediate one of the misconceptions, you avoid all the inherited bugs and faculty procedures as well." (Rethinking University Teaching, p. 38).

To come full circle, a commitment to addressing and fixing misconceptions is a recognition of the power of conceptual thinking in learning. The ideas associated with human constructivism gives us a way to think about what Laurillard calls the "conceptual apparatus," and it gives us tools to both help students think conceptually and for us to gain insight into our students' understanding of the material we ask them to learn. It is both a theory of human learning and a set of strategies to use in the classroom that are likely to help us teach more easily and more productively.

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