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1994 Book DidacticsOfMathematicsAsAScien
calculus before, during, and after algebra.
3.4. Reflections on the Scenario and the Linking of Representations A few features of the scenario (which involves simulations and activities designed by the author and under development) deserve further attention. First of all, it reflects an underlying reformulation of the subject matter of calculus in the spirit of Kaput (in press) and Nemirovsky (1993). This re- formulation regards calculus as a strand in the curriculum beginning in the early grades and continuing through the school years through a gradual pro- cess of formalization and elaboration. Calculus, as the mathematics of change and accumulation of quantity, is conceived as anchored in and growing from everyday experience and also as the context in which much other mathematics can and should be learned, including mathematics such as algebra, which has historically acted as a prerequisite. However, the criti- cal point here is that the linking technology (after all, the windshield view is just another linked representation of the simulated motion) and the phe- nomenological richness of the simulations are regarded as the critical en- abling features of the scenario. While activity structures are important, the ability to connect these structures to more formal representations in “real” time is something new, unavailable before computers with substantial pro- cessing and display capabilities. At a more detailed level, the reader will notice the depth of the connec- tions between significant mathematical actions – comparison of functions – JAMES J. KAPUT 393 REPRESENTATION AND AUTHENTIC EXPERIENCE across representation systems. The windshield view and accelerator embody a certain form of those actions borrowed from the authentic activity of driv- ing, while the formal version of those comparison actions in the graphs are very different. The act of comparing functions in formal representations is not easy, although, as envisioned here, it is tightly anchored to driving a certain distance from the school bus, and one can imagine putting further constraints on the situation so that the students would need to maintain the distance between their car and the bus between particular bounds, reflected, perhaps, in a certain band on the position-function graph. Of course, a major question is whether the strongly situated forms of these activities can yield widely applicable knowledge, whether the “horizontal” linkages of actions (in the sense of Figure 3) at the physical level can yield flexible structures at the mental level. The current work of the author assumes that this will not come easily, but will need to be built systematically through combinations of careful variations of the simulations themselves and physical activities distinct from simulations, including work with MBL devices. One must never forget that a particular action is an embodiment or an illustration of a general relationship only for those who already cognitively have that relationship. For those who do not, it is merely one more action. 4. THE CONTINUING EVOLUTION OF REPRESENTATIONAL OPPORTUNITIES I shall close with a broader perspective on the representational issues dis- cussed in this chapter – what is really happening in these newer interactive media, and what are some of the challenges facing those who would exploit them? 4.1 Redistributing Sources of Structure and Action From the Mental to the Physical Realms One can view the long-term historic development of physical notation sys- tems, especially action systems, as a redistribution of the source of structure of activity from the mental to the physical realm. Recalling my earlier point, that mathematical activity involves tight cyclical interactions between the mental and physical, important shifts take place when one introduces new structures in the physical material with which one is interacting. In a novice learner, these shifts are by no means automatic. They require extended in- teractions leading to assimilations and accommodations wherein constraints and supports embodied in the physical structure are gradually internalized as mental structure. The movement from oral to written culture illustrates the point most vividly – structure could now be “stored” outside the human cortex, although it does not exist or function as structure apart from an ap- propriately structured mind. Similarly, the development of algebra as an action notation system made possible the inheritance of powerful means of quantitative reasoning, and 394 Leibniz’ notations for calculus likewise made available an immensely pow- erful system of thought. In some sense, the most potent intellectual contri- butions, leading to cultural inheritances, are embedded in these “ways of worldmaking,” to borrow Nelson Goodman’s phrase (Goodman, 1978). Some of the most important work of the masters is embodied and handed down, not in the form of facts or even theorems and principles, but rather in the syntax of the representation systems that they enable us to think with. 4.2 The Subtle and Fluid Nature of Representational Activity: Challenges of Representational Uses of Technology Recent work by Hall (1990) and Miera (1990, 1991, in press), together with close examination by the author of student problem-solving in multiplica- tive contexts, exposes a level of subtlety and fluidity in student production of representations that may be difficult to accommodate in traditional styles of computer-based representational activity. Microanalysis of much repre- sentational activity, of which the above references supply abundant exam- ples, reveals that representational elements change their referential mean- ings over time – the same inscription comes to be used in a new way as it is elaborated a minute later and becomes part of a larger whole and as either the mental structures evolve or as the producer’s intentions change. Hall (1990) defines what he calls a “representational niche” – an evolving orga- nization of inscriptions that affords computations and inferences that the user would not be able to make without those affordances. Such contain “slots” for variables that the user often manipulates and recombines or even abandons as activity progresses. All of this is deeply embedded in activity and communication and cannot be considered apart from its embeddedness. And it involves free student production of their own notations rather than the employment of complete, coherent structured systems developed by others. Furthermore, particularly when modeling activity is involved, with physi- cal materials in a group situation, then reference tends to become distributed across the notations, the physical material, the conversation, and the short- term memories of the participants, all in a very fluid, changing manner. The modeling and problem-solving is constituted from negotiating this “fluid.” Aside from the challenges of building coherent accounts of such complex activity, one is forced to ask how the inherent structures of most computer- based approaches to representation, including those discussed earlier in this paper, may constrain, distort, shortcut, or undermine these productive pro- cesses. These remarks are in close alignment with the perspective offered by Lesh (this volume). The author wonders, with some trepidation, whether the egregious oversimplifications of artificial intelligence and the ways that these interlocked with the technology constraints might be repeated as we now deliberately attempt to use technology to augment human capability and learning in the representational dimension. So we are faced with yet JAMES J. KAPUT 395 another version of the eternal question: How much to “give” students (notational structures in this case) and how much to enable them to construct on their own? And the answer may, as usual, be a compromise, because, after all, student time and intellectual resources are limited, and they simply cannot produce, within the genuine constraints of schools and schooling, what required the greatest minds of civilization centuries of accumulated effort to produce. We need to identify the genuinely important and widely applicable representational strategies and find ways to cause students to build these as general, but personal intellectual resources. Looking more specifically at the role of electronic technologies, we must be careful in exploiting the representational potential of these technologies not to produce another version of the oversimplification errors of the artifi- cial intelligence community. They adopted models of mind and of mathe- matical activity that were grossly oversimplified versions of actual minds in actual practice, and have, by and large, had only marginal impact on real education, despite two decades of effort. We cannot afford to ignore the real subtlety and complexity of authentic human experience. 396 REPRESENTATION AND AUTHENTIC EXPERIENCE REFERENCES Bochner, S. (1966). The role of mathematics in the rise of science. Princeton, NJ: Princeton University Press. Cajori, F. (1929a). A history of mathematical notations. 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