Alchemy in the Clrssroom
Many of the chemists and chemical engineers who teach a t universities can be called educators-others should be called alchemist-professors. There is a way to distinguish an alchemist from an educator-the test is given below. You can try it on yourself or try to imagine how a colleague would answer these questions. Alchemist-Educator Quiz 1) Most faculty participate in the department selection of the courses which are offered to their students. Do these professors also participate in the department preparation of a. set of basic goals or a b&.ic philosophy for the curriculum offered to these students? Yes, No. 2 ) Most faculty participate in the department selection of the specific subject matter content of each course. Do these professors also participate in the department preparation of a set of specific oonbent-performanoe objectives for each concept an the content syllabus of each course? Yes, No. 3) Normally, a professor selects the textbook far the course(s) he teaches. But does he also evaluate an alternate to the textbook (for example, a. programmed text) before he makes his selection? Yes, NO. 4) Most professors teach their clesses using the traditional lect,ore-textbook-homeworkmethod. Did thev select these
eomse? Yes, No. .5) Class time is usually spent in m e of two ways: a lecture by the professor or the analysis of single answer problems. If teachinn aids were available so the student could learn content &et.erial outside of class, would the professor use class time for the diseussia~~of open-ended problems? Yes, No. 6 ) One of the objectives of a college education is to teach students to think for themselves. Iloes the professor design his course to teach the st,udent to think a t specific co~nitive , levels such as zaalysis, synthesis, and evduation? Y E SNO.
Most educators would answer yes to all six of these questionq. An alchemist would probably say no to all of them, or he might ask, "What are basic goals and what are content-performance ohjectives"? The alchemist ratringof a professor can he determined by the number of no allswers he gives. The closer that number is to six, the closer the professor is to being an alchemist-professor. Now that we have learned how to identify an alchemist-professor, we should define his characteristics. His title indicates that he is related to a medieval scientist, the infamous alchemist. What distinguished the alchemist from the scientist or engineer of the ISGO's? Each man entered his laboratory to perform scientific experiments. Each knew what he would do. Each could sometimes predict what would happen. But hardly ever did the alchemist know why the results occurred. He had no valid theory on which to base his actions. He had no valid theory to test his results. Whether his experiments failed or succeeded, he had nothing to help him decide what to do next.
opinion Many of the chemists and chemical engineering professors you know can probably he characterized in exactly the same way. Each alchemist-professorenters his classroom to teach. He knows what he will do, he can sometimes predict what will happen. But hardly ever does he know why the results occur. He has no theory on which to base his teaching. Whether his experiments fail or succeed (or perhaps we should say whether his students fail or succeed) the professor has no theory to help him decide what to do next. Surely, the alchemist-professor recognizes that good chemistry and good engineering require both intelligent intuition and a sound base of theory and practice, hut he fails to recognize that good teaching also requires the same basic inputs. Educational Objectives
To be fair to the medieval alchemist, we should point out that he had no valid theory on which to base his work. The same cannot be said for today's alchemistprofessor. For some reason he has not learned about the existing theories he needs to properly perform his work. For example, the alchemist-professor has not read the first four books listed in Literature Cited (1-4). These four paperback books are a minimum booklist for an educator and can help the alchemistprofessor move from medieval to modern times. They can help him begin a career of effective teaching. Mager's book (I) on ohjectives is an easily read programmed text which develops a single concept: the preparation of content-performance objectives. This book is listed first because the ability to prepare these objectives is basic to all course planning. When the professor finishes this book, he should know that a proper course objective is a statement which describes the behavior or performance of the student who demonstrates that he has learned a specific content objective. Note that this is not just a subject matter outline. It is a list which describes what the student must be able to do to show that he has learned. The preparation of these ohjectives is especially important in a course such as thermodynamics, because the subject matter is so complex. I n fact, a major weakness of most thermodynamics courses is that neither the teacher nor the student has these organized objectives available to him as he works. Essentially all thermodynamics textbooks are weak for the same reason-they are not based on a set of objectives. A programmed text is likely to he superior to the usual text because it is built on such ohjectives (G). The second book, Bloom's "Taxonomy," (8) explains one method of organizing these content-performance objectives into six levels of cognitive activity: knowledge, comprehension, analysis, synthesis, and evaluaVolume 47, Number 5, Moy 1970
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tion. Although other psychologists have suggested alternate ways of doing this job, Bloom's book has the advantage of providing many examples of test questions which can be used to measure the student's performance a t each level. Sander's book extends this concept to the questions the teacher uses in his classroom. The table shows how the ideas from these two books work together. I n this table, the six cognitive levels are Levels of Educational Obiectives and Sample Questions Level 1-Recall informotion otout o Conccp&(Knowle&a) Eaoh student should 1,s able to recall and state. write or identify specific terminology, facts, relationshbs, methoda, prinoiplur and theories related to a given oonoept. Therefore, eaoh student should be able to A. write the basic entroov euuation B. ~ e f i n ethe u s e of th; entropy function. C. Draw the P-T-S and T-S diagram8 for the isobaric. isothermal, and adiabatic proeeaaes. D. State the relationship between Q and the area on the T-S diagram which equale S T d S . Leuel 2-Use
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the concept to conolusion, predict trend, or determine an answer. Therefore eaoh student should be able to A . c ~ l c u l ~ st efor a p i ~ mp m e s s that is reversible, partially or totally irreversible. B. Draw the T-S diagram for a given prooess and identify the area which represents Q. Leud 3-Chooae
the Comet Conocpt and Uae it Coriectlu (Appliedion)
A Carnot engine running baokwhrds is a refrigerator. Draw the appropriate diaerams for a proeera operating between O'F and 120°F. 1 atm and 5 atm. Identify appropriate areas and oalooiate va1uw of the shsft work and heat transferred.
sign, for a course in thermodynamics, has been described (6). This course is based on the philosophy that an educated person is distinguished by his ability to recall, manipulate, and apply concepts and by his ability to think for himself; think logically; respect evidence; and apply analysis, synthesis, and evaluation to the solution of meaningful, real-life, open-ended problems, using divergent thinking or induction. The levels of educational ohjectives for this course are shown in the table. The educator believes he should teach students these abilities and that he should serve as a model and guide to the student who is learning to think for himself. The educator also knows that he cannot play the role of an educator in an alchemist-type course, and this is where the fourth book, McKeachie (4), is of value. The hooks by Mager ( I ) , Bloom (Z), and Sanders (3) help the teacher organize the content of a course in a logical manner a t the appropriate cognitive levels. McKeachie's "Teaching Tips" provides a basis for selecting teaching activities which suit the established ohjectives and the chosen cognitive activity. This book is much more than the title indicates. It is not just tips, hut rather a description of the wide variety of teaching techniques that exist, along with an explanation of which technique is suitable to a given ohjective. Each recommendation is supported by a description of the pertinent psychological or educational research. Thus, after he finishes reading McKeachie, the professor should he ready to complete the table shown in the figure. Using the completed table he can begin to select teaching techniques which suit the needs of his students and the design of his course.
Level K-sunthcsis Each student should be able to combine the elements required to form. pattern or struoture not &early there before. The synthesis procurs may result in the production of a unique communication, a plan, n design, a prposed set of operations or a set of hhstraot relations. Leu41 0-Eooluolion of a Dcdp" Eaeb atudent should be able t o make purposeful judgment. about the volue of ideas, works, solutions, methods, materials, design.. etc. using stated oriteria and standards in his appraisal. T o demonstrate his ability at levels 4. 5 snd 6,the student should be able to solve a orablem auoh as the one that follows.
defined in terms appropriate to the scientist or engineer. Then, each level is illustrated with one or more questions about the second law which can be asked in class or used on an examination to measure the student's performance a t that level. A chart to aid in the selection of tewhing techniques,
Basic Objeclives
Many professors are quite surprised when they first discover Bloom's analysis of cognitive levels. Although they themselves are intelligent men who use all six levels, they have not organized their teaching to help their students learn to think a t specific cognitive levels. When a professor does discover and begin working with Bloom's levels, he often finds himself examining both the philosophy and basic goals of each course he teaches and those of the whole college program. If he carries these activities far enough, he may begin to see that the proper way to build an educational system is to design it to achieve specific basic goals. One such de370
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McKeachie (4) also points out that the higher level cognitive objectives can only be taught through discussion and practice. If a professor does not provide for these activities in his class, if instead he lectures to his thermodynamics students, we can conclude that his course probably has the very limited objective of simple recall. Of course, it is possible that there is no other way to transmit the necessary information to the students. If this is the case, i t is most unfortunate, because the limited time available for student-teacher contact is too valuable to waste transmittinn information.
The educator uses class time to help his students learn how to think. He knows that thinking is a skilled performance which he can and should demonstrate, but which the student must also practice. The educator knows he must guide the student's initial trials, provide feedback, correct inadequate responses, reinforce appropriate responses, suggest better techniques, and help the student learn to evaluate his own work. McKeachie (4) describes the course that provides for this type of activity when he says, "The ideal class would begin with a problem which is so meaningful that the students are always a step ahead of the teacher in approaching a solution." A professor can free class time for these important thinking activities in several ways. First, he can prepare and give his students a set of objectives for the material he plans to teach. This act alone will change the way he approaches the course, and it will provide the students with a better base for their studies. Second, he can free a major portion of his class time by using programmed instruction, which can transmit information to the students more effectively than a lecture or a textbook. Finally, he can carefully examine the course content to determine if it is possible to eliminate part of the material traditionally covered and thus free class time to develop thinking behaviors which are more important. This cut in content is really no loss, because the students taught in a traditional course remember only a small fraction of what is presented. However, the professor who uses this free time to discuss the application of thermodynamic concepts to meaningful open-ended problems, can actually expect to make a net gain in both student understanding and learning. At the end of the semester, his students will not only remember and understand more of what they have studied, but they are more likely to be able to use thermodynamic concepts in subsequent courses (7).
Summary
To those who understand it, thermodynamics is an exciting subject which unlocks all sorts of scientific doors. To the student who studies it for the first time, thermodynamics is a miserable mess of mystifying mechanics. It doesn't have to be that way. This paper describes some of the ways each professor can help change it. These are: Mager's content-performance objectives, Bloom's taxonomy of cognitive levels, Sander's classroom questions, McKeachie's teaching techniques, programmed instruction, basic goals, and educational systems design. The professor who reads the four recommended books will find that educational theory is not as solidly based on experimental results as chemical or chemical engineering theory. But it exists and he can use it effectively to advance his profession. The choice is there for each professor to make-which will it be, the classroom of an educator or an alchemist? Literature Cited (1) MAGER, R. F., "Preparing Instructional Objectives," Fearon, San Francisco, 1962. (2) BLOOM, B., IT AL.. "Taxonomy of Edocational ObjccLivos: Cognitive Deomain," Mc Kay, New York, 1963. (3) SANDERS, NORRIS M., "Classroom Questions What Kinds?," Harper and Ilow, New York, 1966. (4) W. J.. "Teaching . . MCKEACHIE. - T i.m. " D. C. Heeth & Co., ~exington;Mass.; 1969. (5) WALES,C. E., Journal ofEngineering Education, 59, (March, 19691. ,~
(6) WALES,C. E., 'rProgrammed Thermodynamics," McGrawHill, Nepi York, Val. I & 11, 1970. (7) WALES,C. E., ChemicalEngineering Education, 2,129 (1968).
Charles E. Wales Director, Freshman Engineering West Virginia University Morgantown, 26506
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