Programmed Instruction in Chemistry
Jay A. Young1
King's College wi~tes-~arre, Pennsylvania
An invitation to participate
Auto-instructional methods which sometimes use meclranical devices iucorrectly called teaching machines2 are based on the technique used by Socrates ( 1 ) . The matter to he learned is presented in an orderly way, from simple to complex, from what is known to what is to he known, in a manner which insures that the student, will actively attend to the presentation. If the student is momentarily distracted, instruction ceases, and resumes only when his attention is again directed to the exposition. The new aspect of Socrat,esl technique lies in its adaptation to large numhers of students, without the necessity for the actual presence of a teacher. When this technique is used, the elementary instructional content of the classroom lecture can be decreased and the topic of the moment can be treated in in greater depth and made morn interesting, thus encouraging students to learn more on their own,
' Preoared in eonneetion with a research oroiect at Earlham ~ollege'supportedin part by a grant irom the US. Oflice of Education, Dept. of Health, Eduration and Welfare (Grant vn .. .. i-12-nzfi . .- .-. .nn) ..,. Dr. John F. Baxter has suggested the term "tutorial instrument"; since this term more accurately describes the concept discussed here, it will he used in place of the less frlicito~tshut currently popular term, "teaching machine."
outside of class. Additionally, herause the student,^ are better prepared, those who do hare difficulties can be helped more efficiently in person-to-person conferences with t,heir teacher. As a result, the attentiou given t,o the individual student mho needs help is is increased in quality, with less expendit,ure of time. This article has been prepared t,o encourage the participation of other chemistry teachers in the preparatiou
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Figure 1 .
An easily made tutorial instrument I t e m h i n g mochinel.
Volume 38, Number 9, September 1961
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of auto-instructional material and to stimnlate its wider use in the instruction of students. Day has discussed ($2) the use of scrambled books in which the student selects a response from a given list of choices. The other major auto-instructional method requires the student to construct his own response. This is discussedain detail here. One of the simplest tutorialinstruments, andoneof the most satisfactory for initial use by a teacher who wishes to learn how to prepare auto-instructional material, can be constructed (3) from a sheet of s t 8 paper and a set of 4 X 6 in. index cards4 (see Fig. 1). On each card a question, a statement, or other instruction to the student is printed. Each card in the set is numbered serially, and the packet of cards is placed, arranged in order, in the pocket on the front face. Usually the information on the first card will introduce the student to the topic to be considered on the underlying cards; and most of the cards will present questions to the student. The first question, on the first underlying card, is easy to answer. After studying this question, the student writes what he believes to be the correct answer on a piece of paper and then withdraws the card'from the pocket. The correct answer is printed on the lower part of the card and is thereby revealed; the student compares this answer with his own response and then addresses his attention to the question on the next card, now uppermost in the packet of cards remaining in the pocket. Each question, and particularly its answer, leads to the question on the next card, in an ordered fashion. Instead of questions, if the orderly presentation of information requires it, some cards may carry statements or special instructions. In some cases, a question may be correctly anmered in more than one way. These several correct answers may be printed on the lower portion of the card; one of these should correspond to the answer written by the student. An answer, revealed by withdrawing the card from the pocket, can be followed by a statement which qualifies the answer or extends its significance beyond that indicated by the question to which it applies directly. A complete series of statements, instructions, questions, and answers, arranged in order, is called a "program." One question from a program set up on index cards is illustrated in Figure 2. Teachers who prepare a program for the first time are usually surprised by the results. The students learn little or nothing from the program. That is, the steps from one question or statement to the next are "t,oo large." A program originally containing 20 discrete questions and statements must be altered so that 50-100 steps appear between the first item and the final conclusion. The almost universal reaction of teachers who have been through this regimen is the realization that before writing a successful program, they did not know how poorly they taught. Put another way, the teacher who learns how to write
1 wish to acknowledge the helpful critioisms of Professors 0. T . Benfey and John A. Barlow, of the Departments of Chemistry and Psychology, respectively, at Earlham College during the preparation of this paper. 4 A dimensioned sketch for the eonstruetion of this instrument from a manila folder will be supplied upon request.
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a program is in closer touch with the student a t every step along the way and is therefore a better teacher in the classroom and laboratory. The first draft of a program, on index cards, should be given to one or two students who then go through the program in the presence of the author so that he can obtain maximum benefit from this first evaluation of his work. During and after this first tryout, the program should be revised by removing some of the original cards, by adding new items, or both. Then it can be given to one or two more students and revised again. At this time the students can be given an examination to determine whether they have reached the objectives intended. After a further revision, the material can be reproduced by mimeograph or other means and the several papers stapled together. A few such programs are available upon request.= For a sample program, also see the article by Skinner
(4).
In general, it is helpful to the student using a program if he is first told, by an introductory statement on the first card, what he can expect to learn from the program. Such an introduction should recall to the student some concept with which he is already familiar and briefly indicate that,, with this as a starting point, he will learn about another concept. The new conce~tis then described in the introductory statement:
Figure 2.
Sample card.
It is important to remember, in writing one's first program, that it is intended primarily to teach, not to test, the student. Hints and prompts that lead to the answer are legitimate and useful. For example, an item might read: Just as an increase in temperature (other variables being held constant) causes an increase in the pressure of a gas, an increase in the quantity of gas confined in a oontainer of fixed volume will cause an in the pressure, when the temperature is held constant. 'Professor 0. T . Benfey, Earlhsm College, has programs for these topics: The Geneva System of Nomenclature for Alkanes; The Geneva System of Nomenclat.~re for Alkenes, Alkynes, Diems, and Cyclic Hydrocarbons. These programs are available from the author: Logarithm (a review); The Patentiometer; Electrolysis, Faraday's Laws, and Numerical Problem; Glass Blowing (end to end, tee, and ring seal); The Barometer and the Weight of the Atmosphere; How to Set and Read a Mercury Barometer; Vapor Pressure; The Boiling of Liquids.
As in any person-to-person discussion between teacher and student, a program should contain items which review 01 expand the concepts learned from prior items in the program. These can vary from simple review questions to statements which require that the student apply information learned from a prior item while new information is presented in the item a t hand. Or, differences between facts or principles that have been presented, and qualifications of the implications that might be drawn from facts or principles, previously discussed, can also be treated in items which review or expand previously learned information. Often, in writing a program, it is necessary to introduce a new subordinate topic. These should not be introduced abruptly. A transitional statement, indicating that a new subject is to be considered, and why, is usually necessary. These, and other helpful suggestions on program writing are discussed more fully in two papers in Lumsdaine and Glaser (6). (The other papers and abstracts in this excellent reference also will be found useful to those interested in auto-inst~ctionalmethods.) As stated above, most beginners who write their first program find that they have not included enough separate steps in their program. Upon revision, the question is: How small shall the individual steps be? There is no clear answer yet known. If the steps are very small, no doubt the program will be clear, but it will also probably be boring to some student. One answer to this unsolved problem is to strive to word each item, no matter how small or large the "distance" from the preceding item, so that a student can realize a sense of accomplishment when he constructs his own response. Edwards (who favors the use of small steps) has suggested that each item in a program should be written in a manner which maximizes active participation by the student and minimizes exposition by the program writer (6). It may be true that this criterion is more important than either the criterion emphasizing a sense of accomplishment or the criterion based on the distance between items. There are other answers to this question. Some have found it desirable to write three programs to cover the same objectives: one with large distances between items, one with intermediate distances, and one with small distances. This procedure is no doubt satisfactory, but it requires considerably more work. Another alternative is to use a "branching" program. Depending upon his answer to a question (usually this will be a multiple choice question) or upon his own estimate of the difficult> he is encountering, the student is directed to go next to item "Q" instead of item "R." Item "Q" then leads the student through a series of small steps, ending finally a t item "S." The other alternative, item "R," goes directly, in one step, from "R" to "S." As another alternative, a program can be written only for the moderately rapid learners; these individuals, m turn, are then paired with slower learners while the slower learners work their way through the program. I n the process, if they are asked to do so, the better students will discuss the points that are difficult for the slower studeuts a t the time they are
presented by the program, acting as apprentice Socratic teachers, to the benefit of bot,h. To many, one of the most cogent objections to the use of a program as a teaching tool is that students who are taught by this method will not learn to read an ordinary text or reference book with understanding. There is some evidence to contradict this conclusion, but it is probably also desirable (and there is no reason to exclude this procedure) to insert instructions a t appropiate places in the program which direct the student to refer to a specific place in a specific book, or to find and study a reference (for example, in THIS JOURNAL or other suitable work, as an encyclopedia or reference book) which is only vaguely identified. The next item in the program itself would, then, refer to the material learned in such an excursion. Conclusions and Recommendations
By using several diierent programs, each treating a particular topic, and requiring that these be studied before class as an adjunct to the material assigned from the text, a chemistry teacher can treat these same topics more fully in his lectures, or he can use t,he now available class time for a discussion of new topics which should be added to the curriculum. Less time will be used outside of class to help students who find it difficult to understand the topics being presented, and fewer students will need such help. However, a great deal of time is required to prepare, to test, and to properly revise a program. One teacher, working alone, cannot easily take full advantage of this method. Those who are interested in developing programs in the field of chemistry are invited to communicate with the author who will attempt to set up a clearing house of information in this field. A brief descriptive statement listing the major objectives that the program is intended to meet, and a general statement describing the content and mentioning unique points,B should be furnished (less than one page of typescript should suffice). These will be reproduced and distributed to all who cooperate, for their information. As finished programs are developed, this author will, if informed, advise all other participants of the availability of such works. Literature Cited (1) Jowerr, B., translator, "The Dialognes of Plato," Random L., House, New York, 1937, Vol. 1, pp. 361-6, or GCTHRIE, "Plato, Protagoras and Meno," Pengxin, Baltimore, 1956, pp. 136-8. (2) DAY,J. H., J. CHEM.EDUC.,36, 591 (1959). 13) A ~ X A N D EH.. R .AND GILPIN.J.. ~ r i v a t e~omrnuni~&tion (4j SKINNER, B: F.,' Seiaee, 128, 969 (1958). (5) LUMSDAINE, A. A,, AND GLASER,R., editors, "Teaching Machines and Programmed Learning: A Source Book," Dept. of Audio Visual Instruction, Natl. Educ. Assn., Washington, D . C., 1960, pp. 401-15, 486-96. (6) EDWARDS, W., unpublished work for the USAF, cited in FRY, E. B., BRYAN,G . S., AND RIGNEY,J. W., "Teaching Machines: An Annotated Bibliography," At~diovi-1 Cornmmiealion Review, 8, No. 2, 35 (1960). For example, in a. program discussing some aspect of acidity, the choice of H+or of H.Of should be stated; or, in a. program on the solution of gas law problems, the use of P V = nRT, of PV/T = P'17'/T', or other appropriate equation, should be indicated. Volume 38, Number 9, September 1961
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