m the forum Symposium on Revolution and Evolution in Chemical education
The Teaching Laboratory through History Miles pickeringl Princeton University, Princeton, NJ 08544
Laboratory education has an ancient and honorable history, traceable at least as far back as Liebig's lab in 1820. While Liebig's laboratory was clearly much more like a present day graduate research group than a teaching lab, chemistry always has been a "learning-by-doing" subject. Influential in the development of the teaching laboratory in America were Ira Remsen (I)and Charles Eliot (21, a professor of mineralogy at MIT who later became president of Harvard. Eliot wrote a textbook in 1867 which became the standard work in the field. Interspersed with the text are 260 experiments which could be done either as demonstrations or as laboratory experiments. Laboratory work has enjoyed long cycles of popularity, and then periods when it was neglected. In the early years of this century, laboratory education was seen as an important extension of learning through doing, championed by the progressive school movement. But in the 20's and 30'9, a controversy was in full flower between the advocates of laboratory and those who felt that "demonstrations" were better. The "demonstrations" advocated were not razzle dazzle big bangs, but rather lecture experiments in which the teacher would collect the data for the class to analyze (3-9). The controversy was submitted to educational research study, but no definite differences were found (1&12). The statistical work, however, was poor by modern standards, and small differenceswould not have been detected. In any event, the lab won out, perhaps because chemists themselves remembered enjoying lab, or perhaps because it was easier to organize (and potentially less embarrassing)than doing demonstrations. It also is fairly clear that faculty life was much more leisurely in the pre-war period than it is today. As faculty become busier, laboratory work could be delegated more easily. The 50's and 60's were an era of great flowering for the teaching laboratory Avast expansion of the fraction of the population going to college, and the "baby boom" demographic bulge led to large laboratory courses, with all the attendant problems. However, beginning in the 70k, lab requirements began to be reduced, and the chemical education community began to lose interest in laboratory education. Westheimer has put it well: "The decline of laboratory is an unstated conspiracy between students who do not wish to take lab and faculty who do not wish to teach it" (13).
means. One indicator is the number of new lab experiments published in this Journal. The data for some intervals of time are presented in the table. Through the early 80's, the proportion of editorial pages devoted to laboratories declined. There has been an upturn recently, not a reversal of American productivity as much as an influx of foreign papers. Prizes and awards also give information about areas of a field that are "hot" or "cold." Aside from the James Flack Norris Award in 1986 to Mayo and Pike, it is difficult to remember any recent recipient of a major national award in chemical education whose contribution was primarily in laboratory instruction. This may reflect a lack of innovation, or it may reflect a deeper sense that to teach you must lecture. Nothing else counts. Laboratory education also has come in for a lot of scholarly criticism. The most important article on this subject is a review article that appeared in the Review of Educational Research in 1982, by Avi Hofstein and Vince Lunetta (14). This review article is especially discouraging,because the authors are clearly pro-lab people hunting for a justification for labs, in spite of their scholarly detachment. Unfortunately, they show that labs have little measurable effect on the educational achievement of students. At first, my reaction was one of incredulity. But the more I have looked at labs in this country, the more I have come to feel that Lunetta and Hofstein are probably fairly close to the tmth. The average student in the average lab has precious little chance of benefitting from the experience. If Hofstein and Lunetta are right, there are three reasonable courses of action: (1)We cango on with labs as they are, because while they do not do much good, they do not really do any harm either. Labs take a colossal amount of time (divide your enrollment per semester by 54 and that is the number of person years wasted by your labs), they contaminate the environment, and they do not add to the acceptability of science courses to our clientele. Laboratory Experiments Published in this Journal
Period
Percent Foreign Authors
Experiments/1000 Editorial Pages
The Present State of Laboratory Education It is dimcult to measure the interest of the chemical education community in laboratories, except by indirect
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(2) We can drop labs entirely, except for the training of future scientists. But how will future scientists know whether they like science, without trying their hands? There is some statistical evidence that one of the main reasons for students to choose to maior in chemistm is the excitement of the lab (16).A decision to drop labs should not be taken liehtlv. Once the labs have been converted to research space: the cost of putting them back when fashions change may be prohibitive.
(3) We rnn try to improve. We can take the point of view that there is nothine intrinsicallv"imoossible about a eood . lab course. It is l i k g ~ a c hjust , music that is hard to play well. We need to distinguish between the music and the skill with which it is played. The Future of the Laboratory
Pressure on laboratories exists not only from competing technologies (including audiovisual systems and computerized experiments), but from the sheer cost of a highly labor-intensive activity. Social issues like animal rights, toxic wastes, and other liability also have an effect. To the degree that the laboratory is purely descriptive, then the same pedagogical work can almost certainly be done more easily in some other way. Serious problems exist in stailing university laboratory courses. The language problem of many teaching assistants is one manifestation of this. (I suggest that, aside from the 60's. America alwavs has been a net imwrter of scientific manpower. Until fairly recently, however, most scientific immigrants were European, so they were not as noticeable.) Also, often the people put in charge of laboratory programs are people who have failed at other enterprises in the department. Frequently, for example, the deoartment concludes if you can do research, you do iesearch. If you cannot doresearch, then you teachlecture courses: and if you cannot succeed at that, then teach lab. ~ometimes,people in charge of laboratory programs are professional lab managers given only a marginal faculty status and a peripheral role in the departmental family. These people are not just second class citizens, very frequently they are hardly citizens at all, and their news are ignored by the department's power structure. At one time, such positions required some solid research experience, but now one sees many ads for MS-level people. We have fallen into the trap of having the laboratory (in essence, practice for scientific research) taught by those with little research exwrience. The pers&mel problems are at the root of much of the malaise of teaching laboratories. Expert committees, the NSF, and similar groups charged &th improving iabs, think in terms of hardware and curriculum, rather than tackling the hard problem of making laboratory jobs worthy of good scientific talent. To paraphrase the brokerage house slogan, the kind of labs you have might just depend on the kind of people running them. Will laboratory survive? Probably, but not for the right reasons. Most large departments depend on their service courses for TA suooort and other economic iustifications. As Derek ~ a v e n ~put & it, =Afteran, the fir& two or three vears of chemistrv eraduate school mav be defmed as a financed not by tGe federal governwork-study ment. but bv the involuntarv subsidv of the parents of undergAduat&" (15). Better reasons can be offeredfor keepinglab. Much data exists that argues that the teaching laboratory is a recruiting device, It is the of the laboratory that draws people into science. This is borne out not only by statistical
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Journal of Chemical Education
studies, but also by simply asking people why they became scientists. It seems to me that if lab is to be justified, the justification is more in the domain of motivation than as a knowledge transfer mechanism. If we end uo droooine lab work in hieh school. for example, studentsire ihkvi&bly going to t k n k of lab as somethine arcane. daneerous. and suitable onlv for a bunch of weiAo specikistsk white coats. ~tudents"neverwill have the chance to discover the excitement of lab, and if the data are correct, that is a crucial motivating factor drawing them into science. P e r h a ~ sit is not accidental that the decline of lab has coincided with the decline in interest in science as a career. Our beginning laboratories do not do a good job as a motivator, because they are too oriented toward measurement. We do too much physical chemistry too soon, especially for a discipline ofwhich the practitioners are 70-80% oreauic chemists. Se~aration.ourfiation. and svnthesis lo&ally come before'measurkAent, and while &ey present challenges, the challenges are seen by the students as more meaningful. Few things are as utterly pointless as measuring something when you are not quite sure what you are measuring, or why. Furthermore, even students not aiming at science as a career need to have some reverence for the technological undertinnines of civilization. In the . ~ a s.tthere . have been manyLhighchlizations that have not evolved into scientific civilizations. The most familiar examde is ancient Greece. Few societies have so well argued-out the basic problems of the human condition, of the relationship between man and God, of man and government, and man and man. Nevertheless, it would not have been pleasant to live in ancient Athens. The difference between the Greek civilization and ours, is not that we understand thebasic problems of man and God, man and government, and man and man any better than thev - did.. but rather that for 400 vears we have revered geniuses and tinkerers in garages In return, the resullne technolow has created a c~v~llzatlon m whlch even the average h-an has a high standard of living. As we eliminate lab reauirements for eeneralists. we are takine a step toward a world in which-scientific tinkering is regarded as work like picking vegetables, suitable only for foreign migrant labor. This is not going to help our nation's competitive position, and it is not goiw - - to help Western civilization. The potential for laboratory is enormous. The laboratory exercise at its best is the fundamental intellectual task of extracting truth from ambiguity, signal from noise. It is a lesson in comparing and evaluating evidence, a central part of intellectual maturity. Unfortunately, many laboratory programs are not taught in a way thatbringithis out. But this should not cause us to abandon laboratory but to improve it Literature Cited 1. Siebting, B.R.;% h a , M. E. J Chem. Educ 1977,54,270. 2 . Eliot, C.;Storer, I? A Manual oflnorgonlc Ckmishy; l u k n , Phi-, New Yark 1869. 3. ~ h e v o n i e r , 'D~..J.Chrm Educ 1983.39, 102. 4. Shrit, D.;Englehart, M.D.Sci. Educ. 1982,16,38W91. 5 . Hunt, H. J.Chem Edue 1955.12,13. 6 . Degelmg, E.F J. C h . Edur 1986.13,371.
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9. ~ulk,.R. J . E ~ U C1 8 ~ 8 . 1 3 . 2 6 2 . 10. B O ~ ~ ~ ; ,M T . J. c k m . ~ d m 1893, . 12, 229. n. Wile, W H. J Educ Psych. IBl8,9,181. 12, ,,,P F. J,c h e m . m u c . 19%. 12,1277. 13. Westheher, F W, ptiwte communication. 14. Hof*".A.; Lune*a,V.N.E m Educ fis. 198% 52,201. 15. Dauenpol* D.A J Ckm.Educ. 1884.62.33. 16. Geolge, B.;Wystraeh, G. B.;Perkins, R.J. Cham. Edvc 1985,62.501.
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