Television for the modern chemistry classroom: Tested applications

Television for the Modern Chemistry Classroom,. Part I. Tested applications. An X-ray film reader as seen on television. This emphasizes theadvantages...
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W. ROBERT BARNARD The O h i o Stote University Columbu., O h i o WITH

E. F. BERTAUT University of Detroit Detroit, Michigan

Television for the Modern Chemistry Classroom, Part I

ROD O'CONNOR' Advisory Council on College Chemistry Stanford University Stanford, Colifornio

Educational television offers the teacher a real potential for improvement of teaching, reinforcment, motivation, and learning. Once considered a stop-gap medium for understaffedschools, television has emerged as a working communication tool. Although experience over the past ten years has clearly demonstrated that students can learn as well (and in some situations, better) from television instruction as from more conventional teaching, the subjective judgments of students, teachers, and administrators have ranged from enthusiastic to strongly antagonistic. Many complex and expensive experimental programs have been discontinued; however, further innovation is suggested in the use of television in the chemistry classroom or laboratory. Table 1 lists some schools which have made use of television instruction in chemistry. This paper2deals with four ways of using television in college chemistry-complete televised lectures, prelaboratory instruct,iou by closed-circuit television, use of live and videotaped television presentations as lec-

Tested applications

t,ure aids in a conventional class, and problem-sessions using two-way audio and video communications. Nn attempt is made here t,o summarize all of t,he programs attempted to date. Rather, four case hist,ories are presented which are generally typical of current experience. Part I1 of this series will discuss new equipment and techniques in detail and part I11 will suggest possible routes for future developments in chemical ETV, describing new programs a t Arizona S t a k University and The Ohio St,at,cUniversity.

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The University of Detroit (E. F. Bertaut) (1964-67) Production and Playback

The course presented was a five-credit, one-semester survey of general chemistry for science and engineering studenh3 Three lectures uer week were presented for an overall average of 43 lectures per term each time the course was given. The lectures were videotaped, without an audience, in the studios of the University of Detroit in the summer and fall of 1964. The director and the engineer were full-time professionals. The remainder of the crew

' Present address: Department of Chemistry, The University of Arizona, Torson, Arisam. 'Additional discussions are given in references ( 1 ) and (8). The text used was Andrews and Kokes, "Fundament,al Chemistry," (8nd ed.), John Wiley & Sans, I w . , New York, 1965. For science majors and chemical engineers this course was followed by a conventional live presentation of additional topics in general chemistry and fundament~alsof quantitative analysis for 5 credits.

An X-roy film reader ar ~ e e non television. This emphorize, the up and mognificotion power of television. Photo compliments of ACI.

of the

EDITOR'S NOTE This article will appear in three parts. Reprints will be hound together and distributed by the Advisory Council on College Chemistry. Information on the distribution will be given with the last part. Individual reprints of each part will be avbilable from theauthor (W.R.B.). Volume 45, Number

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September 1968

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Representative Schools= with Experience in Television Instruction in Chemistrv School

Contact

University of Arizona Rod O'Connor (Tucson) CaseWestern Reserve Maloom Kenney (Cleveland) University of Detroit

E. F. Bertaut

University of Florida John F.Baxter (Gainesville) Kent State University N. V. Duffy (Kent Ohio) Michigan State University (E. Lamina)

Harry Eiok

University of Minnesota (Minneapolis)

Robert Brmted

Montana State University (Baseman)

Kenneth Emerson

Ohio State University Robert Barnard (Columbus)

Oregon State University (Corvallis) Rensselaer Polytech. Inat. (Troy, N. Y.) University of Texas (Austin) University of Wisconsin (Madison)

Wendell Slabaugh

H. Richtol L. 0 . Morgan Donald Gaines

Uses Complete Lectures (Color videotapes) Lecture and Laboratory Demonstrations (live) Complete Lecture8 (v~deotape) Complete Leetures (videotape) Laboratory Demonstrations (videotane). Complete Labor* tory Prelaboratory Instruction Complete Iectures (videotanel ~a'horator): Supplement (Qual.) Lecture, Laboratory

.

Complete Lectures (live) Quiz Sections (live) Lecture and Laborat,orydemonstrations (live. videotape) ' ' Lecture demonstrations (live, videotape) Prelaboratory Instruction (videotape) Complete Lectures (Live, Kinescope) Lecture Demonstrations Complete Lectures Prelaborstory Instruction

' Departments considering the institution of television aids would be well advised to correspond with the schools listed to obtain detaila of advantages and problems encountered. Others who have had experience in instructional television in chemistry are urged to communicate them findings with the authors of this article. were part-time student workers who, however, had undergone a one-year apprenticeship training program before being appointed to crew status. The production facilities included two floor cameras, plus master control room equipment for inserting slides and movies hoth as separate scenes and as superimposed images. The bulk of the "visuals" used in the TV lectures were two and three dimensional plots, models, etc., which were shot from pedestals on the production floor with the two production floor cameras. Posterboard diagrams and styrofoam models were prepared by the TV studio art room for this purpose. Production of each of the 43 taped lectures required 6-10 hr of script writing and 2-3 hr of production time, including story conferences and rehearsals. Each lecture was 45 min long so as to allow lectures to be placed each on a standard roll of videotape. 618

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Journal of Chemical Educofion

The resulting production cost in time, equipment, etc., can be estimated as approximately equivalent to an average full professor's salary for two years. Since it was hoped at the time of production that a t least some of the tapes being produced might be used singly or in small sets, an effort was made to minimize inter-lecture dependence. By this is meant that the lectures were written in blocks of 1 4 by subject matter. Each subject was treated as a self-contained body of material as far as possible. This was done to allow hoth revision of the order of topics on playback and the use of less than the complete set of tapes. Textbook authors will appreciate the limitations of this approach. The playback of the completed tapes began in the fall of 1964. Three complete runs have been made to date. I n the interim six lectures have been retaped. The tapes were played via coaxial cable from the TV studio to five classrooms in a standard classroom building. Each room seated 40-50 students and contained two large television receivers situated in the two front corners of a wide room or a t one front corner and half-way down the side of a long room. One graduate assistant was assigned to each room as a monitor. These assistants were instructured to keep the rooms quiet and orderly, hut to refer all hut the most elementary questions to the students' quiz section instructors or to the lecturer in his office. Testing a n d Evaluation To test the relative effectiveness of the T V course, in the fall of 196.5 half of the approximately 420 students who took the course were randomly assigned to take TV lectures and half to take non-TT' lectures. All lecture sections met simultaneously with the non-TV students in s lecture hall and the T V students in the aforementioned classrooms and were given common hour examinations shout every third week and a final examination a t the end of the semester. In addition to three lectnre periods and an examination time, ertch student was expected to meet aquisperiod taught by a, member of the professional staff and a lab period taught by a graduate assistant using the open-end system (3). Students were randomly mixed in these sections, but neither quiz instructors nor laboratory instructors were particularly aware of which students were taking lectures rria TV. This eliminated any tendency to bias their presentation in any way detrimental to t,he attempt to compare the two kinds of lectnre presentation. The relative impact of lectures presented via TV and in a lecture hall can be compared in two ways. One method is to compare test scores. A second method is to test one's Nielsen rat,ing with questionnaires. Both mechanisms were used in this case, and both furnished enlighteningdata. Grading data were tabulated for all students who completed the course. Examinations were psrtly multiple-choice (49-60%) and partly problem and essay type. Multipltchoice questions were based entirely on lecture material, whereas the problemessav auestions were more ouiz-section denendent since most of

groups. Individual score pairs varied by as much as two percentage points, hut final grade averages were less than one point apart. Grade curves were so similar for the two groups that i t was not possible to conclude that either the better or the poorer student benefitted more from one or the other lecture systems. Student questionnaire forms given to those taking T V lectures were of a standard format given to all student? in TV courses a t the University of Detroit. The questionnaires covered student opinion on classroom conditions, organization of materials, student achievement, and overall opinion of TV courses versus live presentations. A parallel questionnaire was devised by the author and given out in the lecture hall to those receiving live lectures. The student questionnaires reflect the consumers' opinions, prejudices, etc., in an interesting fashion. I t may be not,ed here that most of the students in bath groups had no previous or con-

with ~ollegmtcs r i e w ~POIITSR tawht i n the whirh rc,old be nlremaIl\.e 11, rhcir wvu pr~sentati~mThat ~ 1.0 D ~ W I O W live mur+ i u ct large l c ~ l u r chall i?, TI'- 1 u d w 1 I>ad and vice uersa. Thus their response to all questions was very much based on hearsay, rather than on personal experience. Analysis of questionnaires revealed that, given free choice, a/4 of the "live" students would continue to take their lectures "live," while B/a of the experienced TV-gaers would prefer a live presentation. Thus, both groups showed a distinct reference for foregoing T V lectnres. A requested comparison of TV course preferences showed thst engineering and science students are less willing to accept TVcourses, particularly if these courses are ones which they feel will he most important in their future. This conclusion is not, unlike thst previously stated by Slabaugh and Hatch (4). C I I T T P ! ~e ~ xpwirwe

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I n conclusion it may be stated that under the conditions in which TV instruction was used at the University of Detroit, it appears that most students learn equally well with or without television. One must, however, contend with a sincere student distaste for television in courses which he thinks are really important. Planning for future televised courses in chemistry must consider ways of overcoming this antipathy. It is possible that the use of color television, increased use of close-ups and special effects, and a major improvement of studentprofessor interactions may provide a partial solution.

Montana State University (1961-66) Kent State University (1966-67) The Ohio State University (1967- ) (see P a r t 111)

niques employed. Courses designed for both science and non-science majors were involved, so that lahoratory techniques demonstrated ranged from simple manipulations (e.g., cutting and polishing glass tubing) to fairly complex procedures. Testing and Evaluation Randomly selected groups of students received conventional prelaboratory instruction from graduate teaching assistants. Laboratory examinations and experiments designed to test manipulative skills were given periodically in all laboratories. Results showed that skills requiring close observation of instruction were learned more rapidly and by a greater percentsge of students by television rsther than by conventional instruction. Where more individualized instruction is obviously desirable, in many situations it is probable that short 8 mm film loops available to students will prove valuable as supplements to group instrt~ction.~ Perhapps the most interesting observat.ion concerning the efficacy of televised technique demonstration was t,he measureable reduction in equipment breakage associated with the instruction, a t Montana. thermometer breakage alone on one experiment was reduced by nearly 90% after a televised close-up illustrated the proper method for inserting a thermometer through a rubber stopper. Student opinion surveys revealed that, unlike the usual reaction to televised lectures, opinion was almost unanimously in f* vor of televised demonstrations rsther than live demonstrations hy graduate msistants

Montana Slate University (1962-66) Ohio State University (1967- ) (see P a r t I I I )

Production and Playback

Videotape Presentations

I n an attempt to give all students in freshman chemistry identical and easily observed pre-laboratory instructions, the laboratories were equipped with television receivers located so that students could observe the demonstrations while remaining at or near their normal work stations. The receivers were connected by coaxial cahle to the university's television studios. Initially (1961-65), the programs were presented "live" from the studios by a series of instructors. Subsequent purchase of videotape equipment allowed the instructor in charge of the class to prepare all demonstrations for playback to the various laboratory sections. Television personnel consisted of a professional engineer and director and student camera and control room crews. Because of the large number of sections (15-30 per quarter) and the variety of class times involved, the playback schedule was a major problem. Each demonstration required 2-5 hr of planning and preparation and, on the average, 1-2 h r of studio time. Televised demonstrations were 10-15 miu in length. Each demonstration was designed as an introduction to the experimental procedures to he employed and maximum use was made of close-ups of apparatus and manipulations to emphasize important aspects of the tech-

Videotapes of a few complete lectures were prepared in the television studios at Montana State University for use during the professor's occasional absence. Playback signal was transmitted via coaxial cahle to television receivers7 suspended from the ceiling in the 370-seat chemistry lecture hall. A graduate assistant was present to answer questions a t the end of televised presentations. This method provided a continuity of approach to the subject matter, and the occasional use of such lectures was received without any apparent student antipathy. A more common use of television involved preparation of videotapes or live transmission from instrument rooms or research laboratories to the lecture room. For a typical program the interior design of an infrared spectrophotometer and the recording of an infrared spectrum were taped. The audio commentary was added later as a dialogue between the freshmen chemistry instructor and the instrumental analysis instructor. After the tape was played into the classroom from the TV studio or as part of a live lecture, the instrumental analysis instructor can answer class questions by telephone connection from his laboratory into the lecture hall audio system. Videotaped programs were used in the same way as short film segments as lecture aids. Where the tapes had the advantages of low cost and local adaptation, the live transmission from the research area to the classroom affords a high degree of flexibility.

For additional discussion of prelaboratory instruction by television, see references (5-7). Dr. Wendell Slahaugh, Oregon State University, Corvallis, Oregon, and Dr. Norman Dnffy, Kent State University, Kent, for some time. Ohio, have successfullv used such film su~rrlements .. For more details, see reference (8). See also references (8). , ,, (6). , ,, (7). , ., and (91, , . ' Television rersivers were sumended from motor driven units so that they could be lowered to convenient viewing positions or raised out of the way when not in use by a controlswitch near the lecture hench, ~~~

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Television for Magnification of Lecture Demonstrations

A television camera was mounted on a portable unit near the lecture bench. The camera was used to televise demonstrations using small models, instruments, meters, or lecture experiments not color-depenVolume 45, Number 9, September 1968

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dent. A lecture bench switch selects the local camera signal or a signal originating from the TV studio classroom or video tape recorder. With appropriate lenses on the TV camera and correct viewing distance, all students are able to see a closer-than-front-row view of demonstrations. When combined with the horizontal and vertical overhead projectors and remote-controlled slide and motion picture projectors, the lecture hall television systems allowed for selection of virtually any type of audio-visual presentation to be desired (see the figure).

Montana State University (1964-65)

way communication, is apparently regarded by most students as less desirable than a live system, even when a large group is involved. Conclusions

Sufficient experience has been gained in a variety of applications of instructional television in chemistry to preclude the necessity of repetition of similar experimentation, yet improvements which will make television a more useful tool and more acceptable t,o students are still to be devised. In general it appears that t,elevisionis most useful and best accepted when it serves primarily as an audiovisual aid to improve student observation in the lecture or laboratory and is least useful and most resented when it simply transmits otherwise conventional instruction. It is to be hoped that future systems will utilize television more effectively and that where a situat.ion justifies or requires televised lectures, these will he less conventionally designed and will make much greater use of the close-up sequences and other special techniques of which this medium is uniquely capable (see figure).

For large classes there are three general alt,ernat,ive ways of handling problem sessions. A number of small groups can be formed and these can work with a variety of professors and/or graduate assistants. The professor in charge of the course can work directly with large groups of students. Instructional television can be used to work simult,aneously wit,h several groups or, by use of videotapes, with groups meeting at different, times. Obviously modifications and combinations of Literature Cited the basic alt,ernat,ivesare possible. (1) "Modern Teaching Aids for College Chemistry," serialpobliA technique employed experimentally a t Montana cation no. 18, the Advisory Council in College Chemistry, Stat,e University is described here because it developed Suite 1124, 701 Welch Road, Palo Alto, Calif. 94304. (2) BARNARD, W. I{.., LICO\KSK~ J. J., and O'CONNOR,ROD, some int,erest.ing variations. For optional evening J. CHEM.EDUC.,45, 63 (1968). problem sessions with a large freshman class the average (3) BERTAUT, E. F., J. CHEM.Enoc., 42,563 (1963). at,t,endance was about 500. This group was divided (4) S L ~ ~ A U G W.H H., , AND H w c n , C. V., J. CHEM.EDUC.,35, het,ween t,hc 370-seat chemist,ry lecture hall and some 95 (1958). smaller TV-equipped rooms in another building. The ( 5 ) H w ~ s J. , 13., SCHEMPF, J. M., m n MURNIN, J. A,, J. CHEM. Eouc.. 35.615 (19581. professor worked with a t,wo-camera system in the TV KENNEY; M.'E., TOOMEY, R . F.,AND MARTIN, 3. R., J. CHEM. studio. One camera was used to cover t,he professor Enrrc., 37,256 (1960). while he was t,alking and t,he other camera pointed at a BRA~TED, R . C., J. CHEM. EDTIC., 41,139 (1964). pro,iected image from an overhead projector used for "Teacher-Produced Instructional Film8 in Chemistry," available from the Advisory Council on College Chemistry, displaying the problem-solviug procedures. All viewSuite 1124, 701 Welch R o d , Pala Alto, Calif. 94304. ing moms were connect,ed by portable war-surplus GLEMSER, O., J. CHEM.EDUC.,35,573 (19.58). tclcphme sct,s t,o the TV studio. In order t,o pace the instruction and interact with the st,udents, the chemis: t,ry lecture hall camera was directed at the student group present, and the signal was displayed on a receiver near the professor. This provided the unique experience of roatchiny by television th,e audience who was ~r~atching uou b y television. Comparative evaluations of problem session approaches hy student questionnaires and by comparison of grades on quizzes revealed that students performed measurably worse wit,h the multiple section-multiple instrnctor syst,em and, wit,h a few notable exceptions (unusually competent and conscientious instroctors) react,ed morc strongly against it than with eit,her the televiscd or live large group systems. Although grades New Aids were comparable for studentasin the last t,wo ~yst~ems, therc was a general preference for the live instruction. The newest addition to the Kodak line of Cartransel 35mm slide projectors is the sutomatic focusing model No. Apparently the problems inherent in multiple section 850. This projector rues a light beam reflected from the systems outweigh the advantages of the improved slide surface to control s. focusing motor. Once the first student: teacher ratio when compared to a large group slide in a. series is focused on the screen, the auto-focus syssystem in which the instructor has experience in working tem focuses each slide that reqnires refocusing. The ROwith and establishing rapport with such a group. A slide round tray used on this projector can he interchanged with other models of Caronsel prajectms. Projectors with televised system, even with t,he added features of twoboth remote controls for advancing slides and the autofocusing feature should make possible unattended slide projector operation in seminars, lectores, etc.

s See also referenre ( 7 )

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Journal of Chemical Education