An Audio-Tutorial Approach to the Teaching of Physical Chemistry and Electrochemistry Stephen K. Lower Simon Fraser University Burnaby B.C. V5A 165 Canada Most of us who enjoy giving lectures will readily concede that they leave a wide gap between what we are setting out to teach. and what our students actually learn during these weekl; three hours of nearly uninterrupted discourse. This is ~articularlvtrue if the exposition of the suhject requires a considerahleamount of mathematical argument or reference to graphs, illustrations, or tabulated data. Students vary greatly in the rate a t which they can absorb and assimilate ideas presented in these contexts-let alone transcribe them into a legible set of lecture notes. If the lecture material is based upon concepts developed earlier or assumed as prerequisites, there usually will he some fraction of the class upon whom the value of the lecture is largely lost owing to lack of background or preparation. The strength of the lecture session is of course not in the direct "learninf that it engenders (1,2), but rather in the opportunity toconvey a sense of enthusiasm for the subject, to show its relevance to related suhjects and to place it in its historical. cultural. or social context. In short, we are trying to "sell" ihe subject to the students-to convince them that it is worth learning. If we are able to accomplish this, we generally feel that the lecture is a worthwhile component of the course. and are willing to depend on textbooks, problem sets, and often small-group sectkn meetings in order to provide what the lecture cannot. There is certainly nothing wrong with this, hut it seems valid to ask if this particular mixture of methodologies is the best, or even sufficient, for the task we are setting ourselves. I happen to think not, particularly in the light of the benefits that others have demonstrated in the use of more comprehensive techniques involving the use of audio-tutorial materials (3). mostly in introductory-level courses. The purpose of this article is to show how audio-tutorial techniques can be applied to the teaching of more advanced subjects, and how this can have significant effects on the overall quality of instruction and on the mechanics of teaching the course. The two particular courses to he described here are a first course in physical chemistry, consisting mostly of classical thermodvnamics. and a fourth-vear elective course in electrochemistr;. Although both of the& courses are on the eeneral subiect of ohvsical chemistrv, they nevertheless present rathkr different teaching probi&; &ken together, they offer a better test of the method to he described than would either course alone. The physical chemistry coune is the only course we offer in basic thermodynamics. As such, i t is designed to meet the needs of our chemistry majors, hut a t the same time i t must serve students careers in applied science and some of the biological sciences. Anyone who has tried it is well aware of the difficulty of adapting a course of this nature to the rather wide range of backgrounds and interests common to a mixed group of students, without denying the chemistry majors a sufficiently thorough treatment of the subject. This is nominally a second-year course, hut its reputation for difficulty leads many of the non-chemistry students to put it off until the third or fourth year-by which time their prerequisite courses in physics,~chemistry,and mathematics have begun to lose their usefulness.
The electrochemistry course isa new one, which has never heen offered other than in this format. A s s fourth-yearelective, this course attracts a much smaller but morehomogeneous group of students. The Audlo-Tutorial Method
The audio-tutorial method of instruction comhines a recorded commentary with printed matter in such a way as to nccomnlish a task that cannot he realized as well or as efficiently by either medium separately. In the applications described here, the printed matter consists of what mlght be regarded a s a set of lecture notes. These notes amount to a detailed outline of the coune and cnntain all the equations and graphical material that would ordinarily he displayed in a conventional lecture. There is, in addition, a certain amount of descriptive prose-not as much as is encountered in a textbook hut enough togive the student a general idea of the significance of the &her material even without listening to the tapes. The audiotaoed commentarv is desimed to lead the student through the prkted notes, call& attention to any points that reauire emohasis or are of special interest. Where a series of equations is used to develop a concept, the tape explains the aooroach. mentions the steps not shown explicitly, and re.. minds the student of the ph;sical significande of the various terms. Where graphs or diagrams appear, the student's attention can he called to the various portions one a t a time, so that the meaning.of the total illustration can he grasped in an orderly way. These are all things that one attempts to do in a conventional lecture, but which are probably more consistently accomplished hy this means. There is reason to believe that the audio-tutorial method can be suoerior to the conventional use of lectures and texthooks separately. In order to realize this ootential. care must he taken to exdoit the following special Eharacte;istics of the method: ( I 1 Se11.oarrnc offcrs a n u m l ~ ofadvanaes. r Studentscan do thpir studying at a time end place that suitstheir own schedules and inclinations. Students using the tapes are quick to discover the value of the PAUSE and REWIND buttons on the tape player. If an argument is being developed too rapidly or is unclear, or if attention momentarily strays, the recorded lecturer will happily stop at the student's command, and even repeat his words with no trace of irritation. The fact that these will be thesame words as proved inadequate the first time is clearly a weakness of the system, but at least the student can stop to reconsider what was said, and if necessary to make a written note of the difficulty. ( 2 ) Interaction ofuisuol with aural inputs may have significant effects on learning and retention. 1 am not aware of any research in this field, at least inaseience-teaching conteat. Whatever the efficacy of this interaction may be, it certainly increases the efficiency of the communication process when equations or diagrams are being discussed, mainly by allowing the student to view the item as it is being explained. This cannot be done as easily or as effectively with a textbook, and it works in a lecture only if the student is not too busy iyking notes-and then, only on the one occasion. 13) on verbisee ,-. Limitations . imoosed . bv considerationsof mace and style in a textbook do not exist in th; same way in the audio mode. As an example of the effect of this constraint, it is important that Volume 58 Number 10 October 1981
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students of thermndynamies develop the habit of understanding the physical significance of every partial derivative they encounter. It would he tediousand wasteful of space to remind the reader of R book of the meaning of every such term each time it appears in a set of equations. In spoken commentary, however, thiscan be accomplished in afsirly unobtrusive way, perhaps only as R ouiek aside. ~,~~ (4) The xpreken language, with its el~tnents uf pace, intonatiun and pauses, i i far richer than the written lanwage. By using different typestyles and layouts, one can incorporate a degreeof variation in the prominenceof different psrlsof a written text. If this text is used in connection with s well-designed audio commentary, a far wider gamut of emphatic variation can be achieved. ( 5 ) Students tend to he somewhat hesitant to seek clarification of lecture notes that thev have transcribed in theordinsrv. wav.Since . the printed audiutnl,e notes areentirdg the instructor's rerpon. sihililv, s ~ t ~ l r nare t s far more likrl, re, cwfrunt the instructor whrnsomrthinn is unrlcar o r inernw.Thir.in tum,increawsthe rate at which corrections and improvements can be incorporated into the materials. A well-constructed audio-tutorial lesson can also serve some of the other functions of the lecture, such as mentioning practical applications or saying a few words about the historical development of a concept. Granted that these things are most ideally done in live lectures, I find in practice that constraints of time or diversion to another line of discussion often leave them undone. ~
Using the Audlo-Tutorial Materials In the Course The practical effectiveness of any instructional methodology is strongly dependent on the kanner in which it is interfaced to the other components of the course ( 4 ) . Failure to understand this requirement or to cope with it is probably a major underlying cause of the generally dismal history of most educational innovations, from instructional television and programmed learning through computer-assisted instruction (5). There is a tendency on the part of many instructors to regard alternative instructional delivery systems as instructional "aids" that must remain secondary in importance to the traditional parts of the course, particularly the lecture. This perception, where it exists, is readily telegraphed to students who are typically advised to make use of these aids if they need review, or are having trouble with the course.. .that is, if they are "poor students who want to do extra work." Meanwhile, the lecture remains king. When the new medium is one that bears a large portion of the total instructional load, it exerts a perturbing influence on the other Darts of the course that reauires a reassessment of the role ofeach. With the audio-tutorial materials as described here, the lecture is the most stronalv .. . affected of these components; Its role as an organizing and expository device is made lareelv .~ . redundant by the tapes and the printed materials. One element of a live lecture that is not readily translated to tape is its relative spontaneity: this not only attracts interest, but also it reveals something of the teacher's thought orocesses to the students. The teacher's role as a model for intellectual discourse is all too often overlooked in the development of media-based svstems (6).There is no reason. however, why this element cannot be present in small group meetings or tutorials, which also provide the best forum for questions and discussion pertaining to the course. Since the greater part of the traditional lecture is used for a purpose that is better sewed by the audio-tutorial materials, the time required for class meetings is considerably reduced. Our thermodynamics course was formerly given with three lectures and one tutorial meeting per week. With the adoption of the audio-tutorial method, the lectures have been eliminated. T h e tutorial has heen retained, and another has been added, so the class meets twice instead of four times a week. Electrochemistrv would ordinarilv be scheduled for three lectures a week, but being an upper-level course, there would be no tutorial sessions. In the audio-tutorial format, there are 774
Journal of Chemical Education
no lectures, but the students meet me (usually in my office) for one tutorial per week. T h e tutorial sessions usually hegin with a short quiz, a gentle coercion to encourage students to keep up with the course. There is generally a lot of discussion, much of it initiated by leading questions that I ask. Any particularly difficult or important concepts developed in the current unit of the course are usuallv reviewed: this is best done while displaying tmnspareniie~oftheaudiotape nntes. so that the studenw can relate whnt is heing said to the materials with which they are already familiar. The printed audiotape notes given to the students are the analog of the traditional lecture notes. Some instructors believe that the very process of taking notes can aid retention; it is doubtful. however. if much of this learnine.. . ootential is realized under the time pressures attendant to most class situations. What little published research there is on the usefulness of note-taking suggests that student notes may frequently record less than half of the points which the instructor would consider "important" (7). The students are encouraged to add their own annotations to the printed audiotape notes while listening to the tapes, and also while reading the text. These notes may be clarifications or explanations, or they may be questions: the important thing is that the student has an organized way of compiling this material that relates to the structure and ooeration of the course, and which encourages good study habits. One can get a eood idea of the effort a student is outtine into the course b; the degree to which his Course duide has been marked up! The role of the textbook is also changed. Student reports indicate that the text is used more as a supplement and a reference, rather than the primary source of infnrmation. This has two significant consequences. First, the particular text that a student uses becomes much less imnortant: different students can even use different texts, according Lo individual preference and background, In our physical chemistry course, for example, the "official" text is Castellan (81,hut only those students intending to take further courses in physical chemistry are expected-to purchase it. For the othdrs;some of the more biologically-oriented texts are more interesting, understandable, and useful. There follows from this the obvious second consequence: fewer students need even purchase a textbook. I strongly advise all students to have a text available during the course, but many of them find the good selection available in our library to be quite adequate. How Well Does It Work? T h e most ohvious question to ask about the effectiveness of an alternntiv~teachmg met hod is "how well do the students perform using this method, compared to the traditional method?" This is also a difficult question to answer: it mesumes that one has experimentRl and control groups of roughly comparable nature and of statistically meaningful size. We do not have sufficiently large numhers of students to run such a comparison in any one semester, and the course is continually undergoing modification between semesters. I believe that such comparisons are of rather duhious significance in anv case: thev rarelv even attemot to take into account such variables asattitude and persoiality of the instructor, and oarticularlv what adiustments have been made to the traditional components of ;he cnurse. Even if there is a d~fference, it isdiff~wltto know what t o a t t r ~ h u t eit to. For example, the use of the new instructional method may have required the preparation of explicit learning objectives: if there is an imorovement in student oerfnrmance. how much ~~. of it could be achieved if the objectives alone were incorporated into the "traditional" instruction? I certainly have no reason to helieve that the students in these two audio-tutorial courses do less well than hefore--nor do they appear to do substantially better, in terms of final grades or exam scores. I do find, however, that as the course
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evolves, I am able to place kinds of questions on examinations that I would not have used before; questions that are not necessarily more "difficult," hut perhaps more revealing of one's conceptual understanding of a topic. This illustrates another weakness of the simple "comparison" of two modes of instruction. Most teachers are more eager to teach than to conduct an educational research project and will immediately try to utilize the "new" method for purposes that could not have heen accomplished as easily or efficiently by the "old" method. There is little doubt, however, that most of the students accept this method of instruction, once they have been introduced to it. This latter qualification may be important, because the very small amount of strongly negative view that has been expressed has come almost entirely from students who have not begun the course. Figure 1shows a summary of R ouestionnaire that was eiven to a . ohvsical chemistrv class two years ago. Of thesixteen students who reached the tenth week of the course. nine oreferred this method of instruction, while only two disapproved of it. Although student oerformance and student attitudes are certainly important indicators of thp "success" of an in. structiotial method, the fact that these attrihuteq can he expressed numerlcnlly does not necessarily make them more important than a number of other factors relating in a more general way to the conduct of the course and the role of the instructor. (1) While one might predict the opposite, there is little doubt that persono1 contact with the instructor is increased. This is partly due to the lack of pressure to "get through the material" during the class meeting; student* are not interrupting anything by asking questions, and the whole session can he much less formal. (2) There is more flexibility in accommodating students having special needs, so that the course is accessible ton larger number of students. Students who would ordinarily have to misssome or all of the lectures owing to course conflicts or employment can now take the course with a minimal amount of special arrangement. Students can sample the course before they enroll, and students in other courses can make useof oneor more of the lessons for review. 1 once had a deaf student who was able to make effective use of the scripts used to prepare the audiotapes. Since these courses are modular in nature, students needing toreview somespecial concept while pursuinganother coursecan readily get access to the needed portionsof thesesame materials. Similarly, it would be quite easy to repackage several of the audio-tutorial units to make up a "mini-course" for somespecial purpose. (3) Theprodurliuityof the teacher can he improved. I find that I can offer both of the audio.tutorial courses, plus some other course nf a conventional type, with about the same investment in day to day preparation time as I would require for only two "traditional" courses. (4) Courses whose enrollment is t w small to justify frequent offering hv,. the lecture method can he made available whenever desired. This wns t h v primary reason for mounung our electrochemistry course in thi* h r n l n t : we wuuld normnlly offer thir course once even. t w o years t o perhaps 5-11) otudent.3. Currently, it is offered euery semester to 1-6students. It isevident that many students who take this course would not do so if it were offered at the frequency nornmally dictated hy this low enrollment. ( 5 ) There is far more potential for the gradual improvement of the course as experience grows. As teachers, we have all experienced the feeline that a certain lecture simolv did nut hit the mark.We ~~
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Ouestlonnalre Reswnses ol a Grouv of Sixteen lntroductow Thermodynamics Studenls, Comparing the Audio-iutorlal Based Course with Thelr Perceotlon of How a Slmilar Lecture-based Course Would Rale According to Several Crllerla. no
A-T
"tedure"
metM pefer- m e w bener
Initial exposition of course material Explanation 01 basic concepts Foilowing mathematical derivations Understanding graphical material Ease of reviewing Becoming aware of y a n difficulties Obtaining a clear idea of what you are expected to learn Oppwtunily of ask questions Your performanceon examinations
ence
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6 7
6 5 12 7
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quite easy to make a few annotations on the printed notes or on the sudintapeseript fnr inclusion in the next edition. This can be done not only while the course is being given, but also whenever the instructor comes upon a particularly gwd idea or illmtration in an article or textbook. Problems and Outlook It would only he fair to point out some of the disadvantages of this mode of instruction. From my own standpoint, it is
clearlv the laree amount of time reauired to assemble and the c o k e materials. &ch chapter or "unit" of course material has reauired about 40-60 hr of time to ureoare. Once prepared, addiiional time must he drvoted to improving the materlaln. Mnst t,f my audiotapes seem to have a half-life of only two or three years. Another difficulty, not overwhelming a t Simon Fraser but certainly of concern a t some others, lies in the strategy and politics of convincing an administrative bureaucracy that "contact hours" and amount of instruction provided are not synonymous. One must inevitablv face the auestion.. "if vour method is so good, why are others not using it-including your colleagues?" The onlv answer I can give is that extensive studies h&e shown that ;rnwth in the &ceptance and use of innovations of all kinds depends on a larce number of factom other than the inherent hen&ts the innovation can bring (10); most of these factors are more sociolocical than technological. Moreover, the rate a t which innov&ons diffuse in the-educationol world is especially slow-often twenty to fifty years (11). Since the tape recorder has been available generally for only about thirty years, and the audio-tutorial method of instruction beganin the lQfiOs,its time in chemical education may be yet to arrive. There are twogeneral ways in which further improvements in these courses could he effected. First, audiotape-based materials lend themselves to incorooration of ootentiallv useful learning theories (IZ),such as the "advan~edor~anizer;' concepts of Ausuhel (13) or Merrill's designs for conceot teaching (14). It is likely that these or similardesign ideascan lead to a t least marginal improvement as the units are revised. The second obvious step is to incorporate computer-assisted instruction. In earlier work ( 4 ) , we found that audiotapes and CAI that covered the same material were reearded as complementary by the students, who made he&y use of both media in freshman chemistry. Nbw that terminals having improved graphics capabilities are available, it should be practical to make tutorial-stvle CAI an inteeral - Dart . of both of these courses. One variant of the audio-tutorial method described above might be to key the audiotape commentary to an existing textbook. This would save a large amount of time and effort, since designing and assemhlinpthe printed material constitutes the major part of the preparation of these units. Ideally. one would like to have a text designed especially for this method of instruction. This might soon be practical. The growing availabilitv of word orocessors and variable-font. &nputer-driven iNemnr. in GUc*.Tsarhiq.in'Tompukr.Baa( .Science Inatnrrlinn."lA. Jonnsnd H. WeimWk. FAilonI. PmorrdinpaorNATO Advanced SIWY Innituc. Imuuein-la-neuva. Rclciurn. 197% North Holland Pr-.
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151 ( k u i n w . A. G.."Run. Cornpukr. Run: The mythdory aleducationsl innovation." Harvsrd Vnivanity Pras. l%9. (8) Atk~nxon.G.f.."Dimursr.Curnmuniertian.orReuiwal?"J.C~m.E~~~.Oll2l. 78L786.1976.
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171 Hsrtlcy. J., Camemn A.. "On N o w and N o k . ~ k i w . " Uniuraiti.8 Quarterly IU.K.1, 28 (21,22FZ%. 1974. (81 Clskllan. G.W.."Physinl Chcmialry."2nd. Ed..Addison.Walcy. N.Y.. 1971. 191 Ir,wsr. S. K.. "Audio-tutorid and C A I Aid. tor Prohlsm Solving i n l n u d u w g . Chrmislry,"J. C H E MEDUC.. 47.143-146.1970. 110) Men. Phntt. M.. "Diffuion ollnnovationa." N.Y.. The P- PI-. 1962. N.Y.. Calumbia (11) Eirholz.G.. R-m. E. M.."The N a l u m o l f d u ~ t i o n a Innovation: l University Tea~herr'CoIlc~e. 112) Novak, J. D.. "Rrlcvant Rcscarch on Audio-Tutorid Mcthd8,"Schml Scienrrond Molhemalirs.70.777-7%. 1970. (13) Amubd. D.P.." E d - L i d I'ayphol0gy:A Iknitiv Vim."Holt. RinchanQ Wimton.
