Special Problems of Big Classes Some Common Sense Solutions David N. Harpp McGill University, Montreal, Quebec, Canada H3A 2K6
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bline ~ o i n t sin the course onlv to find the ~ m b l e mwas Class size is relative. For some instructors, a class with oRen a miscopied structure, phrase, or diagram. 30 students is considered large, while for others the numI believe the sinele most useful euideline in teachine anv ber would be 200 or more. There are several courses at " McGill University that number 400 and a few that reach class is to employ a golden-ruleprecept. Do not do anyover 600 (in a sinele -emup). It is uncommon to find lecture thing in the class, to the class or for the class that you would not wish to have done if you were taking the course theaters with a capacity larger than this, but they do exist. For psychology professor James Maas a t Cornell Univeryourself. This "rule" usually will not fail you when a decisity, the term "big c1ass"means nearly 2000 studentsall at sion is needed. once, and this course has an excellent ratmg! The First Lecture The lecture (1)continues to be the dominant method of For the important first day with larger classes, it is esinstruction in the vast majority of small, as well as large sential to have thou~htout potential problems. Issues I classes. S~ecificallv.I wish to address wider instructional have observed includi: where to locate handouts, molecutechniques for the Eiass greater than 200. Unfortunately, it lar models, and other things related to the course, to whom is common to find new instructors approaching their one should consult outside of class, when term tests will be courses in exactly the same fashion in which they themgiven, the evaluation scheme, and reviewing course conselves were taught, thus perpetuating the student as sectent. If these can be clearly and carefully explained, sturetary, busily copying the professor's notes from the blackdents will begin to make a trustful connection with the inboard or overhead. structor. The last thing thev need at this critical time is for It should be k e ~int mind that teachine has a measurable the instructor to be tentativle. Asyllabus and class managecomponent of idibsyncrasy. What is effesive for one person ment outline, along with.crisp visuals, will go a long way can be useless for another. The followine details encomin helping to make the first day proper and memorable. pass some of the features that have worked for me at McGill Universitv for 28 vears. The courses have involved Visuals three levels of introductory organic chemistry as well as The vast majority of university courses, including chemtwo offerines of "The World of Chemistw". a course on istry, are visual deserts. I believe that there are few areas practical aspects of chemistry open to allfa'cultie of the of study not signif~cantlyenhanced by the thoughtful use university (2). The subiect matter can dictate the most a ~ ~ r o ~ r i a t eof color slides. "Chalk-talks" can be a wonderful method of portrayal; however, skill and practice are essential. It kind of presentation. In science, the time-honored method probably is true that for most instructors, the use of slides of delivew has been the lecture. Cherallv. this is true for ". is an excellent choice, because whatever can be photomost disciplines; however, individual tutorials, seminars, graphed (scenes, objects, people, situations) will animate and discussion aouns can work well for small classes. If the classroom. Overheads work well for Drinted matter. one's course a s s h m e n t involves a large class, it is likely but they do not effectively provide much gelp when colo; (assuming an armv of teaching assistants is not available) illustrations are needed. A sinele ~roiector dis~lavine rele" " that the l;?cture method will b;? used. vant pictures that are motivating, informative, or amusing The frst problem (aRer personal lecture note preparain ways that words cannot convey, can help a class enortion). lies in how to resent the information effectively It mously. Humor can be added easily in this way is traditional, thoug6 not always favored by the students, It is imperative that visuals be made at one's own deto eive the a resent at ion (chalk. overhead-assisted) meanpartmentLasopposed to sending them out to the campus inithat the'students take note; at their discretion. audiovisual unit. The total time ex~endedin accom~lishAfter my initial year with an organic chemistry class of ing the job will be less than being involved with uniecesover 500 students, using traditional overhead projecsary explanations and preparations using an audiovisual torlnote-taking lecture methods, I found it more satisfying outsider. and effective for both myself and the class to hand out comThis type of procedure will mean acquiring a camera, plete notes and to use as many interesting 35-mm slides as copy stand, film etc. Many departments have such equipwere needed to stress imponant points. The premise (and ment and modest funds to pay for the expendables. Inreality, is that many students are not accurate note-takitially, it is time-consuming; however, most materials can e n . reeardless of the claritv of the lecture. While it is imbe used effectively over many years and over many po&G that students, as well as faculty, be able to grasp courses. In two to three cycles of a course, one can produce the essence of a lecture and record it in some fashion, the the keys to making a class informative and challenging for information is often too complex to render it to paper in the the instructor and students. A slide or overhead of a currelatively pressured environment of the class. rent, relevant headline not only emphasizes the importance of the topic but indicates that the instructor cares When the student is acting as secretary in a large class enough to point out recent trends. setting, much information is lost, because blackboards cannot always be read effectively and the students cannot such efforts clearly deliver a powerful message to the class that you care about them and about the subiect. The always hear properly simply because of the room size. I effect is that students are much less likely to complain or initially spent many long office-hours going over stum-
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to lay blame for failures in communication. The class will realize quickly that teaching and learning are give-andtake processes where the instructor is doing as much or more than they had anticipated. With such attention, they are more likely to believe that the subject matter is important, thus more likely to take the responsibility to excel. Sophisticated opportunities that are available include computer simulations (3), videodiscs (3), and lap-dissolve projection (4).I have used the latter technique extensively since 1969. There is no doubt that it takes considerable time and effort to prepare such visuals; however, having the capacity to create time-lapse effects and motion in the classroom with these 35-mm slides more than justifies the work. Student reaction to this procedure amply attests to this in demonstrable claims that they can grasp the fundamental ooints raoidlv. " Returning students, having taken the wurse more than two decades earlier, show considerable recall of these exercises. In the area of introductory organic chemistry teaching, the vast majority of stereochemistry examples using molecular models (cyclohexane dynamics, substitution reactions), chemical reaction demonstrations, detailed mechanistic animations, and other sequential effects (laboratory procedures, spectroscopic analyses) can be used continuously and with success. Since the late 1960's, a library of -20,000 slides has been produced. Approximately 3,000 of these are used in three introductory organic chemistry offerings, and about 5,000 more exist in the two wurses summarized in reference 2. These latter classes are videotaped regularly by simply aiming the camera on the screen while the lecture is being given. This simple method provides an excellent record that can be borrowed for student review. In addition, these tapes can be delivered for students taking the course remote from the university. Finally, any of the above material can be made available readily to each student by way of a filmstrip system (5). Performing live demonstrations (6)in class can create hizhlv memorable exoeriences. In fact, even a few such evenis create the pe&eption that more demonstrations were delivered than actually were. This notion likely arises as a contrast to other courses that are taught in & traditional mode.
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Notes "If notes are available, will they still attend class?" If the class is interestine. thev will. There are iuvariablv new items to be mentiked during the lecture that are hot in the notes. As indicated previously, visuals, anecdotes, demonstrations, and real-life references encourage participation and interest. The latter cannot be overem~hasized.In addition, exam performance and class attitude clearly imDrove with substantial class handouts. With notes, the "contract" of what is to happen (class-by-class)is clarified. It meatlv reduces errors. While some students sit back p&sivel$, most, in fact, rewrd their own notes. They are able to take down those ideas that are the "extras" of a lecture-those phrases that glue the subject together. There is time to write down those items because the "essentials" are printed. Advising the class to read ahead helps considerably, as it is then easier during the lecture to know what already is covered there and what else needs to be recorded. On one occasion, upon visiting a biology class, I obsewed a student feverisly copying an overhead projector sheet, writing "proteins are held together by hydrogen." P e r h a ~ sthis was corrected subseauentlv. s -. o.e r h a ~ not. In problem-solving courses, it is rewmmended strongly problems(and a schedule for their completio>j, to with detailed answers in the note package. The students greatly appreciate old exams along with answers and ex-
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planations. Most instructors have access to personal computers; therefore, notes can be up-graded from year-toyear with great ease. These can eventually form the basis for a future textbook and in some instances, even replace it. Exams In no area of teaching are there more idiosyncratic attitudes than in how to organize the evaluation for a course. Essav exams. short answer tests..uroblem exams. and varied combinations of these, (as well as the classic oral), are all methods used for testing. For vew laree classes. multiple-choice exams have beenused for"dec&es. This form of exam has come under criticism since its widened use starting in the 1920's. My own opinion, having used "classic" form of examinations mixed with the multiple-choice method, is that the multinle-choice format serves surorisinelv well if the auestions are straight-to-the-point, fair, and-not too frequekly, if ever, of the type where the answers are mixes of "only a and b","only c if b is false", or "only e if a is sometimes true" etc. Students res~ondwell to auestions that relate to what they have learneb and where ihe language is direct. Using multiplechoice exams, it is possible to question many of the details of the course that ol'ten cannot he done using traditional methods. I find that thc students achieve grades in my courses on written parts that correlate well with those that are obtained in the multi~lechoicesection. This, of course, is not true for every student. Some do have difficultv with the multiole-choice format. or think that they do:~t is not uncommon to hear complaints immediately after an exam that they have "failed" only to find the; performance has been much better than expected. Perception and reality are not always in synchrony. The frequency of exams is often debated. The traditional evaluation format for a course typically consists of "midterms" (one or two) with a final exam and occasionally Clearlv. other assienments. .. .. there is no maeical formula. I conduct my own science classes with three term examsand a final. usuallv oro~ortioned20-20-20-40q. Studcnt evaluations co~si&&tly reveal that the majority strongly prefer three rather than one or two term tests. If the course involves a laboratory, it factors in the grade from between 10-20% of the total. The key feature is to have mqre than one single event to comprise the evaluation. Again, the question to ask is "How would I respond if I were personally taking this class?" The answer is usually self-evident. As of October 1990, it is now required that all McGill University multiple-choice exams be scrambled. The seating has been mandated to be scrambled as well. The reason fa; these measures evolves from the premise that McGill wishes toensure that all exams bc as fair as possihle for all concerned (i.e., opportunities for cheating be reduced as much as possible). Careful studies have shown that when the above measures are operative, no detectable cheating takes place; whereas, if exams for large classes are conducted during crowded classroom time or even during final exams, some flagrant cheatingfrequently takes place (7). One clear conclusion can be drawn with respect to the organization of e x a m for large classes. They must be held outside of classroom time. There is simply no other way around the problem of limited time and crowded, unfair room conditions. At most institutions, there are usually many large lecture theaters that can be booked (well ahead of time) for the early evening hours. Arguments stnnd that professorsdo not have the right to ask the students for exam time after class hours. This does not require debate. Ifwe are involved with a large class, we
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must offer the best for them in every aspect. In my first experiences, when exams were held during class time (crowded etc.), class averages from exam-to-exam varied considerably I concluded that it was my inability to ask just the right number of questions in the limited time available. Holding exams in the early evening (oRen 6:3& 9:00)provides not only a pleasant and secure atmosphere, (with more widely spaced seating), but the opportunity gives the students ample time to complete their test. Under such wnditions, there is less pressure on everyone and a full range of questions can be asked without penalty to those who work at a slower pace. In more than 60,$00 student-exam events over 28 ;ear.;, the only compla~ntthat has been registered infrequently to me, or addressed on course evaiuations, has been that some students feel they are "not the sharpest" in the evening. They are alwavs leased with the "extra time" eiven to complete the exa;. kaving initiated this system, I find thai the grades do not fluctuate much and the overall average increased by several marks over the early tests. For the few students with outside work situations that are unmovable. alternate arrangements almost always can be found. Office Hours
Most professors have posted officehours. If any wurse is oreanized efficientlv. there will be less need for a student t o k i t for trivial points of information. Class dissatisfaction occurs when officehours are awkwardlv scheduled (34 p.m. Tues., 2-3 p.m. Fri. etc.). ~rofessok,oofce hours usually are arranged at times that are convenient for the professor but often not for the student. I have tried regularly scheduled office hours, but in recent years, even for large classes, I have not found the need to have official office times. What works surprisingly well when a student asks for a meeting, is to deal with the question then and there. More oRen than not they hre trying to make an appointment t o ask a question that takes under a
minute to answer. Ifthey wish to simply chat, then arranging a mutually time is called for. The key here . appropriate .. . is to be more immediately available than they expect. Conclusion
All of the former are common sense procedures, but one is more likely than not to find wurses of several hundred students "requiring" several TA's, and even course-wordinators to make them function. With these aforementioned measures in place, one instructor can, in fact, comfortably handle a verv laree class with little assistance. excent for the possible ;se i f help with grading. The effikien6 and productivity more than justify the extra work involved. Summary
Knowledge of the subject matter, efficient organization, as well as a sense of humor are critical. The careful use of visuals on a regular basis, coherent class handout notes and a recognition of current trends help greatly in keeping the course interesting for the students as well as for the instructor. Adherence to the golden rule precept will enhance the information one delivers and make itrewarding and challenging. Literature Cited
1. Croshy, G. A. J. Cham, Educ. 1992, 69, 4 3 3 4 3 6 . Fenster, A. E.; Harpp, D. N.; Sehwsrez, J.A.J. ChemEduc. in press. Z.Fenster,A.E.;Harpp,D.N.;Schwarcz.J.A.J. Chem.Edvc. 1993, 70, 819621.
3. J Chem. Educ: Sofluom, Department of Chemistry, University of Wisconsin, 1101 Univerity Ave. M a d i m . WI 53706. Chom. Edue., 4.Chom.andEng NelusJanuary18,1971;Huhmger,H.:Schulh,H.P;J. 1911.48. 618-620: Daniel, J. S.: Harpp, D . N.: Snyd8r.J. P M e l d s and Motetids 1912.4446; Harpp, D. N.; Snyder, J. P. " h p DissolvePmjectim", McGillUniversity, 1975; Harpp. D. N.; Snyder J. P J Chem. Educ. 1917, 54.88-71; h e , L. W.; Harpp, D.N.: Krakauer, E.: Snyder, J. P J Cksm. Edue. 1977,54,7274: Bodner G. M.; Grembowe. T J;Rohinson. W.R. J Cham.Educ 1980.57,555556;Brookr, D. W. J. Cham.Educ 1984,61,85b859. 5. Harpp, D. N. J Chem Educ 1977.54, 72. 6.Summerlin,L.R.;Ealy. J L J L.ChsmimiDPmonstmfionaASourcpbookforh h o r s : American Chemiesl Saiety: Washingtan, DC. 1985:Shskhashin, B. S.; Chomiml Dpmnstmrions. ~ n o n d b o o kfor nochers ofchemidry; me university ofwi-nsin Press: Madison. WI.Vola. 1-2. 1985. ?.Harpp,O.N.:Hogan,J.J.J Chem. Educ. 1998,70,306311.
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