What con Science Educators Teach Chemists about Teaching Chemistry? A symposium
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Getting Chemistry Off the Killer Course List Mary Budd Rowe University of Florida, Gainesville, FL 32611 Students call certain courses in the undergraduate curriculum "killer" courses. General chemistry is on the list. Failures, drovouts. and reueat rates for nonmaiors in general rhcrn:>tr). equals (81 &ecd:, 3tPi i n man! it~*;irurim;. \InnuIacturlw uruw..it.a with JIS,.& rates like that \wuld S ~ I be out of &siness or he in trouble with the consumers. Indeed, interdepartmental squabbling among faculty members stems in part from discontent over the failure ratesof their students in those killer courses. Sometimes other departments go so far as to offer parallel courses for their own majors--a duplication which is rapidly disappearing in the present economy. Moreover such courses only fuel dissatisfaction on the part of the chemistry department ( I ). Chemistry faculty usually argue that if one learns fundamental principles and theories, one will he able to make applications as needed. (And they often point to themselves as examples of people who use theory to make applications in particular problem situations). In fact. there is considerable evidence that until a verson has "soaked" in the content of a field, partly by being kxposed to a wide ranae and situations. he or she can solve - of vrohlems . only the most superficial of problems. As a rule it takes about 10 years for people to accumulate enough experience to show real facility in dealing with a great many problems (2). For some reason we often act as if beginning chemistry students can do it in one year. There is an expanding pool of research on the teaching and learning of science that could improve the survivor rate in chemistry if it were put to work. This paper presents some of the findings of research which seem to be applicable to the business of learning and using chemistrv. Research results if : q ~ p r ~ p r i , ~ applied ttly lu&n~ survival rate> w ~ t l i ~ :arr~iiang ~ut riwr. I Higt,r withwr r t : w ! ) w l l > l ~13).
sorted, organized and uut into lonz-term memorv. The time
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flow of ideas in a lecture usually moves a t a faster rate than that (2,5). The percent of information loss increases with fatigue-and the more nouel or strange or unfamiliar the content of the lecture in relation to what students know, the sooner the short-term memory or buffer becomes saturated. Wholly new information which has any complexity requires more time for processing than does relatively familiar content. Additional information flowing from the lecturer cannot be processed until the student can make space for it in the buffer by transferring some of its contents to long-term memory.
The Students' Task Most texts intended for the first course in college chemistry introduce an average of 15 concepts, symbols, termsper page. Typically 400 to 450 pages of the text will be assigned over a two-semester course. That means students would have to assimilate 6000 to 6750 units of information, more new language than one finds in the first year of foreign language study-and in chemistry the meanings as well as the words, are new. Moreover, lecturers commonly add ideas, as much as 20% more new material not found in the text. Chemistry texts are information dense and so are chemistry lectures. In lectures the rate a t which ideas must he absorbed u ~ a l l cxrwls \ the C . I ~ H C ~ I Vd t h e hrah I U
