You can't win - Journal of Chemical Education (ACS Publications)

Teaching is a no-win proposition; for every change that is made to curriculum or instruction, some students will be worse off than they were before...
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You Can't Win

The opposite of a profound truth, Bohr liked to say, is a profound truth ( I ) . Similarly, in teaching, the opposite of a useful action-lectures, for example-may be a useful action-a non-lecture course. Continuing experiments with a self-paced physical chemistry course described previously (2) illustrate well a related, probably self-evident Principle of Complementarity: In education you can't simultaneously have both the thing itself and its opposite. Give lectures and students come to depend on them. Stop lecturing and students miss exposures to the personal and omfessional values of dedicated teachers. ~ e c k r eto a class and among the persons assembled those least able to follow easily a rapid flow of ideas must try to do so; even when questions are being answered, most students must adjust their thoughts to that of another person. Hold, however, individual tutorials and the time spent answering the same questions repeatedly may be immense. Stress audio-visual materials and students may not learn to read effectively. Stress the written word and students (particularly foreign students) who do not read English easily are handicapped. Teach diligently via familiar techniques and student evaluations of faculty effort are usually favorable, although-or especially hecause-the course did not challenge them to go where they have not been (3). Endeavor to challenge students, introducing that alienation necessary to all genuine learning (4), and favorable evaluations dmp markedly. Teach year after year in accepted modes and one begins to wonder: Am I being academically responsible? Are there better ways to teach? Try alternative styles of teaching and across the country, one wonders: What's happened to academic freedom? Are there any tolerant colleagues? Hold to "high standards," giving few A's and B's and many D's and F's, and students confirm through efforts expended the low esteem in which they are held and, a s alumni of Traumatic Tech, exhibit little interest in supporting higher education financially. (Athletics, even merely as spectator sports, are deemed more worthy of support.) Award grades for achievement, however hardworking students may he, and one is criticized for rewarding effort. Announce a t the outset of a course a complete set of goals-not least of all, learning to learn without the help of a teacher-and many students may he overwhelmed, and frightened. Intend toward those goals discreetly, by indirection, and some students may never understand what you are trying to do. Specify performance objectives precisely and students perform well on precisely those objectives, little else; few go the extra mile. Specify objectives broadly and many students, uncertain as to what is expected of them, do nothing; they go not even the first mile. The straight-crookedness of learning, like a good walking stick, is usually found, not contrived. Stress course content and, with the short half-life of technical information, emerging students may soon he obsolete (5). Stress how learning occurs and, despite addi448 / Journal of ChemkalEducation

opinion Statistics on a Keller-Type Physical Chemistry Course (2) Fall 1974. 14-Week Term Number of Unit Exams Passed"

Guaranteed Cours Grade"tude"tsd

10 9

Ci

Number of

5

17

Ave. Number of Unit S.D. (and Range)'

Exams Attempted

+

+

6.2 (11-35)

19.9

I 2 8 12 1W TotalNumberof StvdentsStartin. the Courat.

8 7 1-6 Dropped

" In four or fewer attempts (from among five or more version. of each unit exam). Number of exams passed on the first attempt: 535: on the sffond attempt: 263; on the third: 106: on the fourth: 37. A final examination was offered but not required. Sir students raised their course grade on the final (three of the lo's moved to a B; the 8 and two ?'a moved to a C). cOur University is on an A, B, C. No-Credit ayetem. C is the lowest remrded pxde. Note the pronounced peaks a t 14, 11, and 9 exams passed. Few students went an extra mile, and then evidently not intentionally. Only three students were stranded between a B and an A; only Bve (after the final only two) betwee" a C and a B; only three (after the final none) e t h i n two units of the os&e n a d e C.

..

none felt there was time to complete them. Most A-students worked consistently ahead of an A-schedule; many completed their fourteen units in the 12th week oftheterm. Moat B-students worked nearly a t a B-schedule throughout the term. Most C-students fell behind a C-schedule soon after pasoage of a deadline on the first two units and finished with a svrge of hurriedly taken exams the last-and least satisfactorv-week of the term. ' Unexpectedly, A-, B-, and C-level students took on the average the same number of examinations: 20, of which the A students psased 68% a t s ninety to one hundred pareent level, the B students 5 4 % the C students 46%. Students needed on the averaae close to two tries to pass a unit. ~~~~~

tional instructional efforts, emerging students seem no better prepared than other students in subsequent contentoriented courses. Create a self-paced course and you may be pleased that students work harder, learn to acquire new information without the help of lectures, earn higher grades, and smile more: hut have they learned more? Test later to see how behavior has been modified and you may he surprised and disappointed that measured performance on standard, written examinations is no better than that of other students. Break a course into small, manageable units and you are likely to be criticized by students (and colleagues) for not putting it all together. Put it together in review units and a final examination and, if they can get a good grade without doing them, those are the parts of a course most students skip. Allow self-pacing and you have procrastination. Insert deadlines and you lose learning to learn responsibly. Lecture in a self-paced course that contains both pro-

crastinators and eager-heavers and, by mid-term, lectures as course-passing aids or sources of inspiration are out of phase with most of the class. Drop lectures and you're faulted for not fulfilling a teacher's responsibility to a class. Hold small problem sessions to stimulate questions and, mute audience before you, you end up giving lectures. Lecture and those who most need it least often attend. Spoon-feed a class to ensure a healthy start for everyone and well-prepared, lackadaisical students are likely to he lulled into a false sense of security. Step up the pace and earnest, poorly prepared students are likely to become discouraged. Meet classes merely three hours per week and many students lose momentum. Man a learning center fifteen hours per week (within broad limits, the more intensive the teaching the more effective learning (6)) and many sleep-losing, malnourished students become fatigued. Spend extra time tutoring students and you sense strongly a loss of time for other activities and departmental disapproval for letting research slide. Hire help and you are challenged regarding a questionable use of departmental resources. Staff a tutorial center with well-qualified undergraduate tutors to help students with assigned problems (an excellent experience for the tutors, particularly) and you may soon he asked to provide, also, complete solutions to the problems. Create a definitive set of solutions to prohlems available to students for Xemxing, and the use of tutors drops markedly. Grade examinations in a Keller-type course yourself and you diminish the stature of the undergraduate tutors, lose valuable time for other things, and risk becoming more a judge than a teacher. Use tutors for graders and you lose personal contacts with students, first-hand feedback on course materials, and freedom to ask probing hut difficult-to-grade questions. Require sixty to sixty-five percent for a pass, as in conventional courses, and most students learn a little about a lot. Require ninety to ninety-five percent for a pass, as in Keller-courses, and most students learn more about less. Focus attention on physical concepts rather than mathematical manipulations and many students skip over the mathematics. Include mathematical features on examinations and the course is seen by many as merely an exercise in mental gymnastics. Stress science-as-it-is-an institution, ready-made; an axiomatically complete collection of hasic concepts and facts from which all further concepts and theorems can he derived by definition and deduction; a scheme for dishurdening the mind of the need for imagination; a replacement for experience and creative thought-and students may fail to gain experience in inductive reasoning; they may fail to appreciate the time-scale of research and the growth of ideas; they may fail to sense the contributions individual scientists can expect to make to their disciplines; and, generally, they fail to understand the conditions under which creative work flourishes. Introduce via historical and biographical perspectives items concerning science-in-the-making and most students, sensing (correctly) that they will not be held responsible for such material in later courses and on Graduate Record and other national examinations, are impatient to get on with science-as-it-is-at-the-present-instant. Stress prohlem-work and you wonder from the misuse of formulas how deep the students' knowledge is. Ask essay questions and you may discover, in brief tutorials, that many students know more than they articulate correctly in writing. They may write A (e.g., G = G + RTlnQ), say (on prodding) B (AG = AG + RTlnQ), but mean, and use, C (AG = AG" + RTlnQ) Assign numerical prohlems to, in Oppenheimer's words, "calibrate our intuition," and many students get hogged

down in arithmetical details. Encourage the use of pocket-calculators and, just as with arithmetical rules (used as a "black box") it is not necessary to "know numbers" as the ancients did (7), so, similarly, with electronic calculators it is not even necessary to "know arithmetic" or, if affluent, the properties of logarithms. Use exclusively prohlems on examinations and one becomes concerned from the late level in a deductive system at which students begin their work with whether they see the overall picture. Ask for general derivations and everything may be repeated perfectly, except perhaps some "small" item (omission, e.g., of the bar over Cv in the expression Cvln(Tz/T1) + Rln(Vz/Vl) = 0) that in numerical work would often yield grossly incorrect answers. Use strairhtfonvard. clean. cut-and-dried. desk-tvue .. prohlems fo;illustrative examples and you a r e likely to he criticized for beina- d m - and irrelevant. Introduce on examinations "word-type" applications of course content to the real world and you are likely to be criticized for testing something other than an understanding of physical principles. Pop no surprises on examinations, to encourage even the slowest class-members, and you wonder if all the passes are deserved. Introduce exam questions modestly different from assigned prohlems, to develop creativity, and you are met with hurt looks. Offer students two chances to pass examinations and soon they say they would like more than two chances to demonstrate mastery of course content. Offer them four chances and, those taken, some students expect a pass uurelv for "effort". - ~ u d g eexaminations impersonally, objectively, and you fail to acknowledge wide differences among students in goals, background, effort, and the need for encouragement. Exercise personal judgment in assessing performance on examinations (particularly a t critical moments at the beginning of a term) and you are criticized for being inconsistent. Denigrate grades and you're in an ivory tower. Harness the drive for good grades and means and goals become inverted: students work not for good grades to learn but learn only to get good grades. Base grades on easily administered, time- and frequency-limited, in-class examinations and you penalize highly motivated hut slow-working students. Base grades on repeatable, time-unlimited examinations, to reward achievement based on hard work and persistence, and, although grades are on the average higher, surprisingly A-, B-, and C-level students take nearly the same number of examinations (see the table, column 4). Place physical chemistry after organic chemistry and you find that most students have forgotten the general chemistry the physics of physical chemistry is all about. Place physical chemistry immediately after general chemistry and you lose chemistry majors. Place p. chem. still earlier in the curriculum, in general chemistry, and you produce junior-level majors who can do thermodynamics all right hut who cannot write a balanced chemical equation for, for example, the production of silver chloride (and other green gases) to which to apply AG" = -RTlnK. Teach thermodynamics in general chemistry and you haue to teach equation-balancing in physical chemistry. You can't win. For every acquisition there is an equivalent loss. Every aspect of teaching is burdened with features antithetical to it. The charming thing about our enterprise, however, is that with a constructive attitude, nicely described by Keller and Sherman (a), you can improue, and in trying to improve YOU CAN'T LOSE. The well-intended opposite of a good-if imperfect-thing is usually a good-if imperfect-thing. Mutual antagonism and consequent reconciliation is the constant, recurrent path to perfection (9). Vohrme 52, Number 7, July 1975 / 449

Acknowledgment We are grateful to Drs. Z 2. Hugus, Jr., Carl L. Bumgardner, and Richard H. Loeppert for providing departmental financial support for our work on a self-paced physical chemistry course. We wish to acknowledge, also, the recent outstanding contributions to the course of our undergraduate students and tutors Nancy Fleming, Gary Charles, and Jeff Smith.

in "Brerhc on Theatre." IEddor and Tro~lafor:Willett. J.1 Hill and Wsne.NeuYork. 1964, pp. 7L.91ft. 125. 140. 1G6. 151 AmericanSociotvonEneineerineEducation. 1974. " (61 Stravens.P..Dodoius.166(Summer. 19731. (71 Lanaerrc. F.. "The Birth of Mathematics in the Ace of Plato." American Rosesreh Council. Larehmonr. NewYork. 19BI.p.461f. (8) Keller. F. S.. and Sherman. J. G.. "The Keller Plan Handbook," W. A. Benjamin, Inc.. Roadin6 Masrachuxtts. 1974. pp. ri-iii. (91 Lowewonberg. J.. "Hegel Selections." Chsrler Scrihner's Sons. New York. IOB, p. ~"iiff.

(I) B E C ~ ~ B.. .

.

Henry A. Bent and James D. Power1

Literature Cited Bahr. Hsns, in "Nielr Boh?." (Editor RozenCal. S.1 John-Wiley and Sonr. h e . . New York. 1967. p.328. 121 Bent. H A . . J.CHEM.EDUC.. 51.661 119741. (3) Zelhy. L. W Scknce. 183. 1267(19711.

North Carolina State University Raleigh. 27607

(1)

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450 / Journalof Chemical Education

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1 Present

address: Department of Chemistry, University of Pe-

troleum and Minerals, Dhahran, Saudi Arabia.