APPROACHES TO EFFECTIVE TEACHING
"Perhaps i t is not too trite to suggest that all of the excitingnew knowledge, all the important new research, all the great new ideas developed b y our generation and those that preceded us have neither lasting meaning - nor real significance unless-the young people of today and tomorrow can appreciate them enough to use them in discovery and building the better world for 44,489 (1967) which they search."
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Alfred B. Garrett Ohio State University Columbus. OH 43210
Some Stepping Stones in the Grand Venture
"Remember, please, that the search for the constitution of the world is one of the greatest and noblest problems presented by n a t u r e " 4 o observed Galileo. And, today, 350 years later, this is still true. This paper describes some of the stepping stones on the pathway of this grand venture as they relate to the classroom and laboratory efforts of the chemistry teacher in his attempts to teach and inspire students. Perspective and Dynamics
Course planning, teaching procedure, and student confrontations all should reflect the conviction that we are teaching some of the most interesting facts, ideas, and methods of the whole academic curriculum. Our everv move and mode should reflect a contagious enthusiasm for this venture. Examnles of teachers with this tvne of orofessional enthusiasm in'the lirst halft,l'thiscentur)..were'~illiam Lloyd b a n s ut Ohio Statt!, who was ol'tencharacterized as "a chemist u,ith the suul of all evangelist," ;md G . N. I.(wis of the University ,,i Californin of whom it u,ns said. "Yo11 (an literally we the sparks of intellectual curiosity flashing from his hishy eyebrows." There were many others in that past generation. This generation has also had its enthusiastic teachers-Hildehrand, Lippincott, Campbell, Baxter, Alyea, Slaybaugb, Bent, to mention just a few. All too often for our captive audiences in chemistry we have allowed our procedure to make chemistry dull, drab, tough, and unintere~ting. Some of the exciting brain-stretching ideas and discoveries in my lifetime are Plank's theory of quantum of action and the quantum theory Einstein's creation of a theory of relativity Rutherford's discovery of the atomic nucleus Bohr'smodel of thenuclear atom The interpretation of the spectra of elements in terms of the quantum theory and the Bohr concept of electronic energy levels 62 1
Journal of Chemical Education
The theory of why and how stars shine Concepts of our expanding universe Discovery of quasars and pulsars Theorv of the oriein of the elements ( h c e p t s of the d w h k hphx fdlowed by the mechanism of DNA nnd mesiQngtrI l N A in replication uf cells and human eharac~ uf prowins needed for life teristirs in r h mnnufnrturr Discovery of antibiotics These are not only exciting discoveries, but also they serve as excellent examples of the growth of knowledge-where man has had the courage to break out of conformity of one frame of thought, into a new paradigm, great quantum jumps to new horizons of learning and thinking. Factors in the Discovery Process: Creativity Valuable in making this teaching enthusiasm contagious is effective use of two now recognized factors leading to the trigger-tripping process of discovery. These factors can he identified in case studies of discoveries which in themselves have high interest-catching value for students. Attractive, too, for students is the fact that many discoveries have been made by young people-Perkins, discoverer of aniline dyes, a high school student; Hall, discoverer of the process of metallurgy of aluminum, just out of college; Johnston, co-discoverer of the isotopes of oxygen, a graduate student; Curie, discoverer of cause of radioactive process, a graduate student. In the case studies of discovery, a major part of the process can be identified as due to two factors1 (1, (2)
Chance iwors the prrparrd mind; Abilityor habit olwrlng the unusual in therommonplar~-rerendipity. ,,,
o d d W., Saturday Reuiew, February 10,1962.p.
Both of these elements can be cultivated and nourished-a much needed contribution to our whole educational system. Man's potential for creativity is probably his least tapped potential. One of the great compensations of a teacher is to observe the element of creativity unfold in a student's life. Recognition of the Profile of the Creative Mind Not only should the creative potential be nourished in all students hut also those students who have developed this talent should he identified and continually cultivated-if they can be found. But a clear-cut method of identifying creative minds has not yet been developed. Many attempts have been made. MacKinnonZgave a list of characteristics of a creative person as follows:
. . .. ..
They are intellectuallycurious. Thevare flerihlp
They seek recognition and praise. They are antiauthoritarian and unorthodox (Problem: Haw to handle the pseudo or the beatnik.) They are mentally restless, intense and strongly motivated. Thev are hiehlv .. . intellieent. The\. nre gwi1 orwntrd nor mcthud wienred. They prohnhly sl~owcdthew rh~rxctrrisrlcsearly in life.
Equail" difficult to descrtl~rare those methndh useful in stiniulatiny the creative pruress 3.; wt:ll as those that inhibit the prcceis. 11 does seem rather well established that cunformit\. is n seriws inhibitor and vrobleni-vosine: ran lw a s t i m n ~ t o r .Every teacher could research these i n d other factors as he goes about his daily work.
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Tesflna for Creative Minds Here, too, much work needs to he done. A good beginning has been made. I orooose that the followine short test would be helpful to pick'oui the potentially creative chemistry majors a t the end of their senior year. 11 Hun would yw tenrh a Mind man nhat n shadow ir" 2 1 Huu could yt,u ,rpnratr a mixture d salt nnd .ugar without destroying either? 3) Could a neutron gas he liquefied? Why or why not? What would be some eomplic&ns? 4) Assume that the face of the planet Mercury is at a temperature of 450%. and that its oeriods of rotation and revolution are identical !this 12 m.1 quite true INI for simplicir) follow the nssumption,. I'rcdirr some unique rhemicsl suhrt,+ncesycm might find on rhe tncp and bark of the planet t h n t are not found ar such m the plmrt earth. 5) Predict how the following mathematical relationships, much used in chemistry,were obtained-that the integral of the differential equation
is the expression
discipline-both large and small. That was what stimulated Hall, Curie, Urey, and many others. Testing with thought-provoking questions is an important teaching-type of testing but is oft& as usually frowned on by test writers because of discouraging . .results in the prading scale. Examples of such questions might be 1) When sulfur is heated, it first melts then turns to a solid then melts. Visualize the processes and describe the reason. 2) COz is a gas, but SiO2 is a high melting solid. Both carbon and silicon are in the same familywith four electrons in the outer shell. Account far these extreme differencesin the physical state. 3) Zinc is above iron in the ECS, but zinc is used as a protective coating an iron to prevent rusting. Why shouldn't a less active metal be used? 4) Assume you have two bricks, one at O°C and the other at 20% Place them together in an insulated vessel and the resulting temperature will be the average of the two-about 10°C. However, mix salt st 20' with ice and water at O°C and the resulting temperature will be below the lowest of any of the original eonstituents. Explain the reason for the difference in the two cases.
5) Ice cream placed in a refrigeratar at O T will melt. Why does it not remain a solid at the freezing point of water?
6) X is what percent of y? 7) A solution of pH 2 is diluted 1000 fold. What is the approximete pH? Then the resulting solution is diluted mother 1000 fold, what is the approximate pH? Explain. 8) One liter of ozone decomposes to oxygen 2 0 5 30?. How much of it has decomposed when the volume is 116 more than the original oxygen? 9)H20 has a lower mol. wt. than HrS, but liquid H20has a higher boiline ooint than liauid HIS. Whv? 10) ~redic'tihe van der ~ s a lequation s fora neutron gas. 11) Three beakers are placed under a hell jar. Beaker A is % full of water; Beaker B is 'I2full of 0.001 M NaCl solution and Beaker C is % full of 0.001 M sugar solution. At equilibrium what will be the approximate level of the liquid in each beaker? 12) Trace what you would expect to happen to water molecules over the temperature range of O°K to 5,000,000,000°K.
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Courses Should not Only Have Breadth and Depth but also Mountain Peaks Curriculum builders and course devisors customarily preDare to defend their offerines in terms of breadth and d e ~ t h . k e l y do we hear them planning for the mountain p e a k s . ~ u t even, course should have them. Thev mav" he in varied forms. planned and nonplanned, hut, when available, they are expected to be climbed. When Charles Beard, an eminent historian of Harvard University, was once asked by a young instructor (whom later I found to be Dr. George Counts3 of Columbia) if he could summarize in five minutes all he had learned in his lifetime. He answered, I don't need five minutes, all I need is three statements:
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I I Whom rhe gods would dwtrny, they fir~tmake mnd with power. 'I'hr mills ~ , rhr f g d i grind slou.Iy, I~utthry grmd exceedingly
2)
This examination would probably lead to a paradox: grading this exam would prohahly r ~ q u i r3s i rnan)~&eariwideas on the part of tht. proiessor as were required 11). the studcnt in answering the iuestions! The eradine " -.nrocedure would have to he based on an evaluation of the students'ingenious, novel, or creative approaches rather than whether he obtained a correct answer. [Note: To my knowledge the answer to only one (and maybe two) is known.]
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Teaching and Testing by the Thought-Provoking Problem Method The proposed test of creative chemistry majors coupled with the case method of studying and discovery process leads loeicallv to a search for more effective teachine and testine methods. The case method of teaching by the d&covery process speaks for itself. A very helpful addition to this method would be to keep a running list of unsolved problems in the
fine. 3) The bee fertilizes the flower it robs.
A week later he called Counts and said "I want to add another2'4) When its dark enough you can see the stars.
Those were Beard's mountain oeaks in teachine historv for half a century. ~ o u n t a i n - p e a kplanning is Gohahl; the -ereatest challenge - to the chemistrv teacher. The followina- six examples I propose to you as a starter, to challenge your thinking. 1) If you ask nature the right question, you will get the right an-
swer. 2) The cannot be evaluated, but it can be used. 3) Chance favors the prepared mind.
3Privatecommunication. Vo/ume57, Number 1, January 1980 1 63
4 ) Science ir power, hut science has its lim~tmions. 5 , \lethod is rhc hnndmaidcn i d principle. 61 .\Ian is dealing with an wderlv u n w r i e .
I propose we consider seriously:
N o w you arlrl yours-these gu beyond l~alanring equations and iremizine theories whirh are to he sure a necessarv. . rmrt of the breadthand depth.
Interest -Understanding
Prepare a Springboard for Philosophy ~. From time to time be ureuared to be a uhilosonher and in so doing indicate some of the limitations of science as well as the Dower of science. Point out some of the "imuonderables" or "limitations" of man and science and dare to speculate on their significanceThe maximum probable speed The maximum probable energy source The maximum probable observable universe The maximum probable explorable universe by man The origin of life The mechanism of the life process-from inanimate to animate, or from crystal to cell The destiny of man or man's chief end.
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These ideas can be a springboard from the quantitative disciuline of science into some of the as vet unsolved ereat mvsteries or in some cases "imponderables2'-dare to ponder the imponderables-they are good brainstretchers. And Finally Teach to Achieve the Learning Cycle Chemists like cycles. The Carnot cycle is probably their favorite, but here is another-the Cycle of Learning-which
64 / Journal of Chemical Education
t
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Curiosity -Motivation
Retention
1 Creative and Critical Thinking
Much of our activity as teachers has in the past been directed to the first threksteps of the cycle only (i.k., to interest, understanding, and retention), and a t the end of the term we have tested the students primarily to determine their retention. The next three steps are very difficult ones to achieve and to uartici~atein. but thev are extremelv essential to our whole process of education if we wish to develop scientific literacv. We still know so little about creativitv. motivation. and thk stimulation of curiosity that too man;& us lack the couraae to tackle these stem. Nevertheless. enoueh is known of each of these to give u; a good start. B; the end of their experience in our classes, our students ought to have been brought to the place where their curiosity is aroused to such a pitch that they will want to continue the maturation oftheir scientific literacy. Mastery of this cycle can make this search for the interpretation of the universe an exciting lifetime venture for our students and for us all.
