the forum General Chemistry Needs More Resources, Teachers with Attitudes that Enhance Self-Esteem, and Chemical Foresight David W. Brooks University of Nebraska-Lincoln, Lincoln, NE 68588
The "Provocative Opinion" by Klotz (1)in the March, 1992 issue of the Journal summarizes a n enormous amount of human experience with respect to science learning. Science literacy was an issue in biblical times. No group of scientists holds literacy about its discipline in high regard. This same Journal issue contained early writings from the Task Force on General Chemistry (2-5). Several sessions at the 12th Biennial Conference on Chemical Education were devoted to Task Force activities. Uni Susskind described a sort of consensus core curriculum (6). while Orville Chapman suggested using "dynamite" and starting over with a fresh approach (7). During one of the crowded Task Force sessions a t the 12th Biennial, it struck me that activities center on seeking a stable body of content to codify. Chemistry is moving very fast. Educators are having trouble keeping up. My concerns deal with several areas. First, both the impact and importance of computers have gone nearly unrecognized. Second, the issue of motivation has been blurred. Finally, although the main thrust of the intellectual effort expended thus far has been in the area of curriculum, there are reasons to believe that such a thrust won't be successful.
which chemists can make use of expert tools. Several pre(Only one sentations a t the Biennial noted such uses (7,9). reference is made to the use of computer tools in the first Task Force reports published in the forum (10); it focuses upon equilibrium computations for which we now use electronic calculators and procedures with large inherent approximations to obtain outcomes of little actual physical meaning.) Donald Norman introduces the concept of a cognitive artifact (11).somethinr! invented by humankind t h a t 'intetiaces'between humans and their task in such a way as tochonge the cognitive demand of the task. Indeed, cwgnitive artif'acrs lead tocognitive artifactsadinfiniturn. It's time to recognize the computer as the most important cognitive artifact ever to have touched chemistry. General chemistry ought to emphasize using computer tools to solve problems rather than using those computers to learn to solve those problems using memory together with electmnic calculators. The cost of addressing this issue will be enormous. It involves hardware, software, and staff development. Perhaps the NSF should focus its resources on better defining this problem.
Computers haue changed how chemistry is accomplished
Although not (yet) easily described using models for synaptic modification, motivation is as important as curriculum or instruction.
It is logical that a teacher would look a t computers as potential tools for helping students to learn. Chemistry educators have used the computers of today to teach the curriculum (alluded to in ref 2, p. 177). For the most part, college chemistry has not begun to encourage students to learn how to use computers as intellectual tools, as "expert collaborators" whose responsibility in a shared task is to provide a combination of much of the memory and computational skill we now expect students to assume themselves. There has been marked interdisciplinary activity It is along these lines using the Mathematics program (8). appropriate that chemistry teachers teach the extent to
In spite of the fact the we don't see much written about the subiect in the cognition literature. motivation still counts. Herbert ~ i m o n opened the 41st k u a l Nebraska Svm~osiumon Motivation with a systematic discussion of howmotivation underpins currentexperiments and models of cornition (12,. He armed that current unified theories of cognition are incomplete, and indicated how one might introduce features within them to address the missing issues of motivation and emotion. The mechanisms of motivation and emotion are not easily described. It is clear that mood affects learnability I t i s well known, for exam-
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ple, that persons very frightened or stressed are poor learners (15). Whv? One hwothesis is that moods lead to wide scale releases of bra&chemicals that alter the operating environment of the brain. We all know that chemicals& be consumed that alter mood. We also know that there are cognitive links-that the mere mention of a word often brings on smiles or tears. My sense of a key problem with general chemistry is that students, in general, are treated poorly. Also, many general chemistry teachers have lost an excitement for discovery. I lump these factors together under one heading, motivation. As we examine humankind in a social context, a variety of motivations come into play. The way in which students are treated is the cause of many perceived learning problems. Note the 'Colorado Survev'cited in the editorial bv J. J. Lagowski in the same ~ o u m aissue l as the Task F& forum first appeared (16, 17). A consequence of the environment we often provide is that majors drift away from science. They switch: they don't fight for our support. Not only are general chemistry studeLts treated with a sort of disdain, but often so are those who teach them. A simple way in which the environment issue ~ l a v out s is through thetraditional assessments often usedin-introductory courses designed to sort one student from another. Even for those capable of succeeding, there often is diminished self-esteem. The editorial was the most important contribution to the general chemistry debate to appear in the March 1992 issue. It put forth some facts, and laid much of the problem on the proper doorstep. Upon receiving the prestigious Millikan Award of the American Association of Physics Teachers, Lillian McDermott contributed a compelling article describing her extensive, successful research i n 6 physics learning(l8). I was struck by one paragraph included in her paper: There is a critical mndition that must he met for the type of instruction described to be effective.A nonpejorative atme sphere must be cultivated in the dassrwm or laboratory. Mistakes should be viewed as opportunities to learn, and students must be given the chance to demonstrate that they have learned. The grading system has to be made sufficiently flexible to reflect their progress." Reflect upon the cover of the March 1992 issue of the t atoms obJournal (131, which ~ u r w r t sto d e ~ i c bonded tained from "tuden?' equipment. That is a phenomenal observation for a 50-year old chemist to appreciate; a realization of a dream. The accompanying article suggests that hardware from which such '~ictures'can be obtained is within the fmancial reach of many small departments (14). Chemistry still is exciting in and of itself, especially to an expert. It requires no apologists. It does require that chemistry teachers communicate to students what contemporary chemists are thinking about and doing. A 50-year-old chemist cannot expect a 20-year-old student to share this appreciation. However, there is a sense in the writings of chemistry educators that the old-andwell-understood is better appreciated than is the new-andstill-extensively-studied. The chemists I most admire dwell on the unknown, not on the known. Theirs is a search for understanding. Any content-generated motivation in most of the curricula being proposed would seem to come Even though numerous from the known, not the u&o& persons advocate teaching lab, only one speaker a t the Davis symposium described a program where students could engage in the task of being chemistry researchers (7). Why do we stand back from the issue of motivation? This also is a resource problem. Students and teachers need
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Journal of Chemical Education
time; time costs money. We expect students to invest their time, but we don't want to invest much of our time.
Curricular revisions are within our current scope of resources, but their imuact is lihelv to be much smaller than the scope oftheproblek demand. Readers might or might not agree with my first two assertions, but addressing those areas will require substantial reconfigurations of resources. Curriculum revision, on the other hand, is much less expensive and holds what I believe is intuitive appeal for a chemist. Therefore, I want to spend the remainder of this article considering cuniculum. I see spending our intellectual energy on devising a new mriculum that recasts pads of the current curriculum as drilling what is most likely to be a dry hole. Bodner said essentially this (51, but I want to try to analyze the problem from a different perspective. In recent years, the pages of the Journal have included many contributions about learning, and a t a time that drastic revisions of the introd u c t o ~ c o l l e g echemistry cumculum are being considered, it is appropriate that we seek the best available euidance from iearn-ing theory.
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Connectionist models suggest ways to design curricula Edelman (19) convinced me that human learning is based upon the functions of groups of neurons acting in concert. With the cover title "Mind and Brain." the Sentember 1992 issue of Scientific American includes 11a r k cles on this topic (20). Martindale has written a cognitive psychology text from a neurological perspective (21). Churchland and Sejnowski provide a readable, scholarly work in this area (22). The October 9,1992 issue ofscience carries the cover title, "Focus on Neuroscience." and includes a stimulating editorial by Daniel ~ o s h l a h d(23). A description of learning in terms of molecular and cellular events is as exciting to learn as that of any other chemical system (24,25). The connectionist model envisions dynamic connections between neurons involving structures called synapses. The individual synaptic connections are not genetically predetermined. Instead, they form, strengthen, weaken, and disappear dynamically as the result of the organism's experience. Recent results suggest that the redundancies and potential ronnectivitie~ma~ be far more extensive than previously imafined (2fi). The connectionist models are closer-to-the-molecules than those often used to analyze learning problems. Connectionism suggests that, the more related 'things' we can hook a collection of input ~ e r c e ~ t i o nto.s the more likelv that collection is to iakeeense relative to prior expeGence. The connectionist model describes this as "content addressing"; similar perceptual inputs embark upon initially similar paths. Prevlous experience alters the neural environment by altering connections: present experience necessarily is affected by any previous experience because that experience changed synaptic connections. In connectionism, neurons are interconnected, not ideas. The storage of an idea, if you will, is widely distributed over the brain; sometimes, as the result of brain lesions, portions of ideas are inaccessible, and the resulting impairments are dramatic (27). Furthermore, during recall, all of the information related to an idea is not moved to an executive area; it stays put. Instead, the neuronal groups act in a parallel fashion. As I think, I talk to myself, I draw pictures in my mind, and I otherwise function as if there is a hearing, seeing, speaking central executive within me that helps me control my thoughts. For the most part, I can
do only one thing at a time, and many factors determine what I choose (or what I am compelled) to attend (12). It would be extremely surprising if you did not function in a similar fashion. The connectionist model lacks a central executive and is, therefore, counterintuitive. In the connectionist model, as reflected by references 19-26, the software is the hardware! Is a n understanding of connectionism important for chemistry teachers? All teachers communicate with students through sensory perception, and we hope to shape our instructional messages to them so as to bring about student learning. I assume that the more we know about this process, the more likely we are to succeed. Successful teachers talk about relating something we are learning to something we already "know." Although the connectionist model permits a more fundamental explanation of this result than other models do, the outcome is transparent to the successful teacher who knows fmm experience that ideas seem to be connected or connectable. This same point is made by the Task Force using different jargon and models (5). At the end of your general chemistry course, you probably expect your students to know and be able to use these terms: election electron electronegatiuity, electron affinity electroplate, electrolyte The term election and some things about the term electron will be bmught by students into your course. As a teacher, you act a s a neuron modification technologist. When you say or write any of these terms, some of the same perceptive feature detectors (neuronal groups) are activated. Your students' previous experiences, the other words and nictures vou use as vou oresent these terms. and what ask studentsto d; with the terms help determine the seauence in which the students ultimately activate motor neurons that push their pencils or move their fmgers on a keyboard or force air over their variously tensed vocal chords to make use of their knowledge. There even may be changes that we can't see and don't measure, hut onesthat will enable or facilitate subsequent behavior Each student has something on the order of 10'4synapses. Just by being in your classroom, some or all of these synapses will change in ways whose outcomes are both intended and unintended. It is very likely that you have little concern among your course outcomes for the term election. On the other hand, you probably want electronegativity and electron affinity linked fairly closely. I t is not surprisine that Dersons new to these terms mieht find them confuiing. f i a t is why successful instructors will not only define these terms. but also thev will take pains to explicate their distinctions. (To perplex-someone,write out the word 'red'usinrr vellow ink, and ask them about the color.^ ~eachingmaterialin the absence of any context is like teaching nonsense syllables. It can be done, but i t is fairly dif6cult. Children do learn prayers and oaths and poems and speeches with little sense of their meanings. If we want to observe quick results that reflect some sort of understanding, however, i t is best to learn something similar to or related to another already known thing. That's a curriculum desien orinciole. The neurons, not the ideas, are connected. GiL the term election maynot interfere much with the term electron because of the extent of prior learning, you can expect the other terms beginning &th the letters e-l-e-c-t to interfere quite a bit, especially when they all are new to the learner. There are some chemical facts that can be presented without a need to tie them to other chemical facts. My doc-
toral research concerned the mechanism by which tyrosinase, a copper protein, catalyzes the aerobic oxidation of tyrosine to a quinone that subsequently forms melanin oolvmers. Sharing the details of this work with general . chemistry students never seems appropriate. Telling them, however, that tyrosinase is involved in a series of chemical reactions that lead to skin pigmentation (28) and, as a result, helps facilitate the at-a-distance bigotry often experienced by persons of one color from those of a different color, seemed appropriate on many occasions. The chemical fact can be tied to an extant, pre-existing, nonchemical body of knowledge. Ideas don't have to be very chemical in nature to be highly connectable. Connectionist models explain why Ufactsn&pend upon context
Connectionism orovides a n exolanation for the extremely important phenomenon of context dependence. Context dependence is a very powerful consideration when deciding upon the chemistry content likely to be useful a t the turn of this century. While there may be some absolutes in the world, there are no absolutes in the mind of any one persou-a place where there is very little detailed prewiring, vast numbers of synapses somehow store information regarding one's previous experience, and those synapses change with a seemingly very short half-life whether or not they are used (29). Context-dependence plays out in many ways, the most easily demonstrated being in the area of optical illusions (30). The impact of ambient odors on the oerformance of cognitive tasks is (31). nowl ledge learned from nothing less than stu-g studies of oatholoeies and diseases further support notions of contextA(32).~ & w i o u sawareness about how we know what we know is among the more controversial issues being studied in connectionism (33,341. Context dependence affects understanding. Anton Lawson, a leading theorist of the Piagetian ideas brought to science education by Robert Karplus and others, describes large-scale studies from which he posits a "multiple-hypothesis" theory (35)and suggests that:
...tests of formal reasoning actually measure the extent to which persons have acquired the ability to initiate reasoning with more than one specificantecedent condition, or if they are unable to imagine more than one antecedent condition, they are aware that more than one is possible;therefore conclusions that are drawn are tempered by this possibility. In these studies, the context into which a problem was embedded had a profound impact upon the performance outcome. Context-dependence boils down to the conclusion that your knowledge (understanding) of stoichiometry in a slide-rule world is different from that in an electronic calculator world which is different from that in a computer world. When you spend most of your professional lifeworking with saiples nf nanograms (and above! wherein the laws of thermodynamics always seem to apply and variables are controlled in a fairlv conventional. standardized fashion, that 'understandmg-shifts-with-context'is very counterintuitive. That, nevertheless, is what context-dependence means. Context dependence makes some results not at all surorisina. I asked students in a course on instructional message &sign to design materials that would help teach the conceots of four-coordinate holes (tetrahedral holes) and six-coordinate hnles (hexahedral holes, in closest packed solids. First, they suggested using a computer application for renderine" that would oermit students to"make cuts" in the rendered solid. Next, they suggested a series of two-dimensional drawings mcluding colors and overlays for overVolume 70 Number 2 February 1993
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head transparencies (36). When shown one figure from the J ~ u r n o 6' l 7) used far this purpose, they ofired extensive criticism based upon their perceptions of context dependence. and concluded that the firmre would onlv bc useful to thdse who already knew theUconcepts. he; were not surprised to learn that the figure leads to confusion. My point is that asking students questions during class uncovers verv real learnine ~roblemsthat mav have nothing to do wit< chemical cocLpts. I suspect th& many chemi&y leaming problems are of this variety, since we have developed our own language to describe very special cases. Say the word unionized to yourself: did you mean belonging to a collective bargaining organization, or were you thinking about HC1 molecules in a nonpolar solvent?
Well-establishedprinciples guide the design o f ordinarv tasks to make success on them easier
Whenever performance counts, humans try hard to restrict thinking tasks. We practice. We rehearse. We try to make the implicit more explicit to facilitate remembering it. For situations that we deal with regularly, we try to keep the demands on ourselves from being both deep (i.e., havine extensive seauences of well-understood ~rocedures but that usually require considerable expertise to apply) and wide (many choices) (38). The most challenging problems we face in life are both wide and deep. Naturally, we hope to educate students to deal with those kinds of roblems. The success of humans on such problems, howeGer, is usually low. One might say that early Task Force curriculum proposals trade a wide curriculum for a deer, one. Experienced teachers implic4tly understand that a i d e , derp curriculum ends U D being u n t e a c h a b l ~ v o ucan't "teach" both width and depth. As soon as a d e e ~ curriculum emerges. those of us charged with teaching such a curriculum All proceed to develor, explicit algorithms that enhance our students' ability-to skcceed. ?hat is, we'll figure out ways to "shallow" the deep curriculum. Any learning that cannot be connected to prior learning stands out as do nonsense svllables. Even though the word 'connect'is misleading (the neurons, not the id'as, are connected), successful teachers connect new ideas to existing ideas. In a deep curriculum, the successful teacher will be trying to link related ideas by noting similarities and differences. In a wide curriculum, new ideas are related to less similar ideas through such links as broad patterns, personal experiences, economic realities, etc. Deep curricula are well suited to concept development, but most concept development in today's general-chemistry courses is focused on skills development. Computer tool use mitigates against the need for developing these skills. The meaning of the term ''understanding" depends upon contexts. Something is understood as judged by an e&ernal observer relative to some standard held by that observer. Each of us who teach chemistrv has a standard for understanding. In fad, research on misconceptions is common~lacein science education todav (39). There is even a notitin that misconceptions onen are "misapplied conceptions" (40,. Some writers i m ~ l v that a deer, cul~iculumwill lead to better understanding. Maybe, maybe not. In a sense, we already have sacrificed a better understanding of the big picture of chemistry in an attempt to achieve a better understandine- of a few of its parts. Trading wide for deep is not necessarily a good idea. Perhaps this question will help to frame the issue: Which ice cream store do you want to visit, 30 flavors, three dips, or three flavors, 30 dips? Perhaps that's a way to describe a likely outcome of proposed depth-for-breadth alternatives.
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Assessments motivate core curricula There is a curriculum. Most of the bestwelling college general chemistry textbooks are better described by commonalties than by distinctions. Curricula exist for many reasons. There is the sense that the organic chemistry teacher should know what knowledge is available to students as a result ofgeneral chemistry. There is also a sense that success is somehow measurable on the basis of criteria such as standardized exams (ACS) or professional exams (GRE, MCAT). In fact, curricula of quite diverse proportions have been tried many times over the years. Brown University under Leallen Clapp (41) taught organic chemistry to freshman beginning in 1948,a curriculum that partly has been rediscovered (42). CalTech tried some very innovative laboratory curricula in the early 1970's (43). Chapman's description of the current majors' laboratory a t UCLA is downright exciting (7). There has been no shortage of new ideas or approaches to curriculum. One is hard pressed to find any special evidence that graduates of innovative curricula went on to any uniquely greater glory or suffered untoward consequences as compared with graduates of more conventional curricula. This lack of evaluative data may have more to do with the expense of appropriate longitudinal studies than anything else. Also, when we think about Norman's notion of cognitive artifacts and consider the dvnamic nature of the business chemistry is about, it is likely that, by the time the outcomes of a well-designed and ngcessarily expensive study of a curriculum innovation are in place, the need for revisions would already be a t hand. Assessment based upon a curriculum provides a source of comfort to an instructor. It is a way of saying, from an external perspective, 'what you are doing is okay.' So, assessment has a long history in the Division of Chemical Education, especially as reflected by the activities of the Examinations Institute. When we try to analyze what we are about in terms of individual learners, one-at-a-time, assessment tied to some core is not really as important as is finding ways to present challenging problems such that self-esteem is raised rather than lowered in the process regardless of the student's performance. If there is one thing general chemi s t courses ~ all too often are noted for, it is lowerina - - student self-esteem. Let me point out quickly that, in college chemistry teaching, some form of assessment is needed. Especially for beginners, learning for the sake of learning is a weak motivator. College teachers usually use grades as motivators. If there are no conseouences connected with attendinn to chemistry learning: then there is little likelihood ;hat chemistry learning will occur. Offeringchoices and offering repeatability may make a big difference. Teachers who do not have anv formal assessments usuallv are dissatisfied with learning outcomes. Using differentinstructional strategies may have more impact upon general chemistry than will revising curriculum Bodner makes the point that an alternative to revising curriculum is to revise instruction (5). Examples abound. There has been substantial research effort to indicate that teaching verbal descriptions before writing equations leads to better learning results. even on formal nroofs (44). . Using cooperative learning strategies wherein students work in teams better reflects current research ~racticein industry (45) and also appears to have some v& reasonable learning outcomes (46.47). Repeatable tests make a big difference(48,491.
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lb enhance peneml chemistry, liberate students from trivia,>hallenge them with the unknown, and help them improve their self-esteem It is easy to slip into the view that a curriculum core of principles; understood from singular perspectives and invariant over time, is something well-trained persons of good intent can create. It's a tight idea. Curriculum is a natural rallying point for chemistry teachers seeking change. Curriculum, however, is not our biggest problem. Our biggest problem is lack of resources, and we have undertrained and underequipped faculty as a result. Scant resources lead to inappropriate attitudes toward students. We don't s ~ e n denoueh time meetine student needs. We should be kying to acquire the hardware, software, and training so that we can teach students how to use comouter tools to deal with chemical problems. We should be ;sing more time to devise indiiidualized programs of study and creating challenging problems to evaluate students In the absence of resources, we are forced to focus upon the areas of curriculum and instruction. those least likely to produce important changes. Given that, respect the unknown and extol its challenges! It is possible for a biotechnologist to use medium conditioned using buffalo rat liver cells as an ingredient in a growth system even though its workings are not well understood and just because experience tells us that it makes the system more efficient. Why is it that some of the catalysts used in coal desulfurization and liauefaction require pretreatment with Has and continuous addition ofsmall amounts of that sulfur-containine substance to be effective? It is okav to tie chemistry threais to the unknown, because that isUwhere the most exciting part of chemistry is going on. Develop national experiments-general chemistry experiments wherein students perform the same task and pool data in an attempt to solve some national problem. For example, restriction analysis of genetic material from bees might be an excellent way for students to help document the distribution of Africanized honey bees. Discover Internet; link students to one another. Use repeatable tests. Instead of looking to the classical content divisions to draw descriptive examples, look to the chemical industries or chemical phenomena within 50 miles of your campus. Even if we cannot make com~utersa maior " .art of everv course, we can replace the skills programs found in student resource centers with tools applications, and provide some opportunities for experience with them. As long as we keep looking inward seethe most stable ideas within our discipline instead of outward toward those ideas that are most in flux at the edee, we put our least exciting material forward, not the most exciting. In . that Cha~man'sdvnathe face of this a ~ ~ r o a cIhsus~ect mite suggestion is the most appropriate one for improving general chemistry.
Literature Cited 1. 2. 3. 4.
Klotz, I. M. J Ckem E d u . I=, 69.173. Rickard, L.H J. Chsm E i u e 1882, 69, 175-177. Hawkea, S. J. J Chem Edue. 1982,69,178-181. S r r n c e r J . N. J. Ckem Educ. 1992.69.182186.
I w1 7 Chapman. 0. L 'Lct'r Use Wnmn~e' paper 127 12th Blcnnlal Confcrena on Chcmmal Educauon. Da\m CA. A u m s 226. 1912. 8 A b a r a a . 1992 .Mu,kemn,tm C r n F r m m . R a w d a m , Nctherland3. September 2 4 IW1 \"p
