teaching aids
W. ROBERT BARNARD The Ohio Stole University Columbur. Ohio WITH
J. J. LAGOWSKI The University of Teior Austin, Texor
ROD O'CONNOR Advisory Council on College Chemistry Stanford, California
The introduction of new or improved equipment which allows the instructor to bring before his studeiit,~ makrial which previously would have been difficult or impossible to present has aroused new interest in the use of teaching aids in the chemistry classroom. However, despite these advances in the development of visual and audio aids, the complementary physical facilities for the new equipment often are lacking. Modifications in existing chemistry instructional facilities and construction plans for new facilities should provide for the automatic projection of films and slides in lighted classrooms, highly functional lecture demonstratiou areas, television, overhead projection, improved work areas for students, and realistic seating capacities. Some current methods of providing these are summarized, along with descriptions of appropriate new hardware, and suggestions for future designs for chemistry classrooms. One of the real problems facing the teacher of chemistry is not what is new, but rather, how can the new be best used? Unfortunately the answer to this quest,ion has been incomplete in many cases or has been dictated by expediency. The introduction into the classroom of programs employing "new instructional media" have frequently been followed by a period of repent,ance when it became apparent that continual eugiueering or concessions to equipment deficiencies were necessary in order to maintain the expected level of performance. Such an outcome is not necessarily the fault of the devices involved, but it is an indication of a problem which may become more prevalent unless the teacher's needs can be expressed in terms which can be appreciated by the manufacturers and other individuals who have the pot,ential to solve the technical problems involved. This paper has drawn on the experience of the chemistry departments of Montana State University, Rent State University, The Ohio State University, and The University of Texas. Work at these schools has left little doubt that most teaching aids presently in use require specific facilities not provided in the couventional chemistry classroom or laboratory. Therefore, guidance in the proper design of learning spaces ~dannedto meet the needs of the chemistry teacher now seems necessary. The goal in each of the schools mentioned wm to give the inst,ructor maximum flexibility in presenting his Presented at the Division of Chemical Edncalion Symposium Development of Teaching Aids at the 153rd meeting of the American Chemical Society, Miami Beach, April 12, 1967.
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The Modern Chemistry Classroom subject. For example, it was desirable to give the instructor the capability to insert into his lecture, mith the push of a single button, a segment of a 16- or S-mm motion picture film or a slide or a segment of a film strip; such segments could be re-run, reversed, or shown in any order, all under the complete control of the lecturer. It was also felt that the instructor should have the facilities to prepare a televison tape of a laboratory experiment, lecture, or lecture demonstration at any time or location he should choose, with an absolute minimum of detraction, such as setting-up the equipment. Such tapes-or live demonstrations presented before a small, self-contained TV camera mounted on the lecture demonstration bench-should be able to be shown to a class with a minimum of advance preparation. For example, there should need to be no rolling in of TV monitors, dimming of lights, nor complicated electrical or video connections. I n addition, measurements such as meter or thermometer readings taken during televised presentations should be easy to record from any seat in the room. Naturally, the approaches used by the various schools to provide capabilities such as those described above have varied; the resulting innovated equipment indicates that the time is right for the college instructor to specify his needs so that the suppliers of equipment can design, manufacture, and market the needed apparatus. The designers of learning facilities can then address the problem of matching equipment capability to the academic chemists' needs. Our experience along these lines thus far has been gratifying. Approaches to Design Television
Most of the experiences with conventional classroom television have been with a number of relatively small sets hung from the walls or ceilings. Installations of this type introduce considerable distracting hardnwe into the classroom. There is available, however, a more ideal system-TIr
EDITOR'S NOTE: This column inaugurates the Teaching Aids psge referred to in the July 1967 editorial. As editor of this page, Mr. Barnard will use his wide experience and knowledge to bring to our readers pertinent summaries of modern andia-visual hardware and suggedions for its rlse by chemistry teachers. This ealumu also will carry film reviews and abstracts of computer instruction materials which arc of interest to chemists.
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1 Figure I. The beginning of the iodine-clock reoction in the 350 seot chemistry closrroom ot The Ohio Stote University. The imoge on the rcreen i. projected from a TV camera mounted on the bench in front of the lecture. Distoncefrom the bock row d reotr where thi. picture war token to the projected television imoge: 55 ft; image size: 9 ft x 12 ft.
projection equipment which :'
is presently capable of shoming a 14-Et wide image at the front of a room with sufficient contrast and intensity that a Beckman Thermometer can be read 60 ft away from the screen in a room with a level of illumination equivalent to 25 foot candles (Fig. 1). This system,' which is presently being used at OSU on111 - to Dre. sent general chemistry lecture demonstrations, can he connected with outside transmission sources to project hlackhoard-by-wire lectures or the output of a computer terminal. With a facsimile copier and Polaroid camera, "hard copies" of televised data can be repared on short notice. An alternate system could use small (9-in. screen) TV viewers at the desk mace for each pair of students Similar to the arrangement used by some airlines. Such ~
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' T h e TV project,or was obtained from Amphicon Systems, Norwood, N. J., and the screen from H ~ r l e yScreens, 26 Sarah Dr., Farmingdale, N. Y. 11735. Further information on ancillary equipment can beobtained from the aubhor from OSU.
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Figure 2. Conrfrvction diagrams of the television recording cart. The small television viewing monitor lSony PVJ-3030 with 5-in. screen1 can be removed, i f necesory, t o o more convenient location. The elevator column unit and pan heod (Quick-Set model 7900 column; model 7201 friction pan head) quickly positions the comero for e i o c t height and angle for optimum viewing. The $mall spotlights attached t o the pan heod (Fig. 201, are "Lampette" low voltoge reading lamps. Detoil 2b shows the removable pin hinge suggested for the cort top; this feature is useful i f the video recorder must be removed from the cart frequently. The cort dimensions are odequote for either the Ampex VR-7000, or Sony EV-200 1 -in. video recorders [Fig. 2d.
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Figure 3. A lecture experiment being video toped in the rerearch laboratory.
systems arc not inexpensive hut their ir~stallationcosts compare favorably with conventional installatioris in a large lecture hall such as the 350-seat lecture room a t OSU. Color TV projectors using laser light sources show promise, and t,he designers of future lccture rooms might keep this possibility ill mind. Camera Facilities. Properly designed facilities for the camera equipmerit allow the iostructor to choose whether t,o prepare the demonstrations and other presentations ahcad of time on video tape or to do them live from the lecture bench, whichever method is most suitable to his material. A portable TV tape recorder for making tapes outside the lecture room can he contained in a cart matching
the lecture demonstration bench (Figs. 2 and 3). One such cart now in use is small (30-in. wide), rolls on swivel casters, can be moved easily down the aisles of a laboratory, and is a completely self-contained closed circuit TV system. The TV camera and recorder with this unit can he operated by one person, as seen in Figure 2. The same unit, of course, can be wheeled to the lecture bench and the camera and recorder connected to the lecture room's TV projection system. To take maximum advantage of TV presentat,io~~s in the classroom, a T V camera might well be permanently installed on the lecture bench. The inst,allation cau be as simple as mounting the camera on an elevator support on the desk top, or as complete as an "electronic module" (Fig. 4) which contains the TV camera and support, TV distribution amplifier, light, and projector coritrols, public address amplifier, wirclcss microphone receiver, and telephone lines for computer outputs. The module is designed to slide into staiidard furniture units, thus converting R conventional lecture bench to a centralized control uriit for all types of equipment. Although these controls presently must be custom made, we suggest that the temptations of electronic personnel to build elaborate displays be stifled. I n our installations, pressing a single button mill turn off or on appropriate lights, run a projector, and if necessary, mechanically orient thc projection xreen. At OSU, the screens are always tilted down with the lights on for overhead or TV projectors; mheu a movie, slide, or film strip projector is turned on, t,he screcn tilts up. The emphasis in the design of the equipment iricorporates t,hc hasic requirement that the iustructor have an absolute minimum of controls t o manipulate. Lecture Demonstration Benches
By using the concept of modular drsigr~for the components of a modern classroom, apparatus now in existence or still being developed by mar~ufacturerscan be installed easily as permanent or portahle units according to the instructor's particular demands. The key here is the design of the front of the classroom. Scvcral suggested designs for lecture demonstration benches and aricilliary equipment are p r e ~ e n t e d . ~ The emphasis is on small, inexpensive nuits, easily moved about and designed for both right and left harided operation. The TOPS and writing overhead projectors (Figs. 5 and 6) are on permanent rolling stands. The "basic" lecture demonFigure 4. The "electronic module" removed from a boric lecture demonstration bench. The drawer detail shows how light and correlated pmjector controls could becombined into o single drawer. The television viewer could berecure if this were a locked drawer.
* Inforrnatio~loil axd working drawings of this equipment are available from the authors.
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Figvre 5. A rolling support for the TOPS projector IAct-A-Matis model AOM-1, Laboratory Furniture Co. Inc., Old Country Rood, Mineola, N. Y.) conveniently f m i l i t d e ~,toring the cells and reagents near the projector; the praiector could easily be moved from the clawoom to a preparation areo for testing demonrtmtionr.
Figvre 6. This rolling support for a 10-in. X 10-in. overhead proiector hor space on each ride of the writing area for notes. The carten should be of the locking type. The slot for the projector d b w r the unit to be lihed up only, for removal. Space for o spore projection bulb i s provided at the bockof the projector.
lions appear on the accompanying screen. The screens should have a slight cant, defined by 40' side angles from the plane of the screens, to improve the optimum seating area. Metalized lenticular front projection screens are suggested to insure maximum image clarity, brightness, and true color rendition. If lighting in the front of the room is concentrated downward. it will not "wash out"
stratiori bench is small (7 ft long) by classical standards; however, it is possible in this length to consolidate all the basic services; electricity (a continuous strip of outlets on a11 four sides of the bench), gas on front and back. down-draft hood, omvision for TV, data-phone, public address system, and projector and light controls. Matching carts with drop leaf extensions fit on either side of the hench if an additional area is needed. If space is restricted, demonstrations can be assembled on Masonite panels in the prep room and transferred to the hench without disturbing the equipment. Several other suggested lecture benchdesigns are shown in Figures 7 and 5. In Figures 9 and 10 we call attention to the two front projection screens, a feature in all of our suggested classroom arrangement,~; this arrangement can be used to optimum advantage if reactions are projected on one screen (TOPS, slides, or motion picture) and the appropriate equaFigure7. Asmallcomplete lecture demonstrationbench ancillary equipment. 66 / Journal of Chemical Education
projectiou booths to modify existing facilities are presented. Figure 11 is a suggestion for a large room where the booth might he installed in a coat room or hall a t the back of the room if only a limited space is available. I n the second design, suitable for small classrooms, a small projector support (Fig. 12) replaces several seats in the back of a room. Both booths feature locked storage space for motion picture and slide projectors, which are equipped with mechanical positioning device.; to insure that equipment will not be misaligned while being set up. The location for projector and screens is well defined in the AC3publication, W I o d e n Teaching Aids for College C h e m i ~ t r y ,and ~ in "New Spaces for L e a r n i ~ ~ g . " ~ Figure 8. This bench could be two 4-h benches with o center aide, or a continuous unit 12-h long with the drop leaves up, or a demonstration cort could be moved into the center section.
the picturc on the screen. We have demonstrated that adequate ge~ieralclassroom illumination to permit note taking can be maintained with a judicious selection of projection screen material, projector locations, and room lighting systems. In addition, adequate space should he available in front of the lecture bench (a minimum of twice the screen width from the screen wall to the front row of seats) to allow for free movemerit. Projection Facilities
To he useful to the instructor, motiou picture or slide projectors should he in place, focused, etc., prior to class. This is much easier with modern projectors than with older types. Designs for two inexpensive 8 - & ropy of this p,,blieatjon be ohtailred born: ~h~ visol.s Cr,lll,nilotl Callege Chemistry, 701 welch ~ ~ ~stanford , j , Ulnivet.sity, Palo Alto, Calif. I .4 r:opy of this pttblicatior~ call he obtained from: E d w tional F a d i l k s Lahomtories (EFL). 4 i 7 i\Iadisou Ave.. New Yo&, N.Y. 10022.
Figure 9. A periodic chart, cholkboord, and two pmjection screens can be permanently mounted in the front of a classroom using this type of arrangement. Note the angle of the wall; odditional cant may be given to the projection screens to facilitate alignment with projectorr. Both out to keystoning of the pictures from the overhead nroiectarr: motors con b e added to each screen to reolian them when ~,~~ motion pictures or slides ore projected.
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Films and Proiectors
Figor- 10.
Two screen projection or used ot Kent State University
A modification of a 16mm motion picture projector can make it considerably easier for the instructor to show short film segments without an operator. The device (Fig. 13), a logic ~ O I I trol accessory, facilitates the completely automatic operation of a projector by adding a sequencer to the mechanism similar to that, on a tape recorder, i.e., antomatic start-stop, re~vind, and reverse. This devicc makes it possible to use short film segments similar to the S-mm film loops in laboratories or classrooms too large for existing 8-mni projectors. The equipment necessary for this type of operation includes a Bell and Howell 16-mm auto-load Volume 45, Number I , January 1968
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Figure 12. A projection cobinet. Equipment mounts on sliding trays which pull out for loading and adjusting equipment. The proiection axir is through the wail; dimensions d the cabinet will vary with the number ond type of projectors required. Equipment con b e stocked, e.g., o 35-mm slide projector con b e mounted on a "saddle" over o 3 1 / r - X 4-in. projector. Working drowingr for this cobinet ore ovoiloble from the o.thor..
Figure 11.
A proiection ,torage cobinet.
motiou picture projector, a solid state logic control designed as a permanent internal attachment for the pmjector,j and a metallic sensing tape to be added to the film. To use this "logic" operated projector, the instructor follows this sequence.
than down thc middle aisles. Cross aisles could he wide enought to :dlow easy access to all the individual seats. The economy of get,ting students to and from their seats in a minimum of time is apparent at examination time. Seating units in the modern chemistry classroom might very mcll be a continuous counter mherc each
1. He places the projector in "auto-load" mode, and turns the projector switch to remole. 2. The project,ov will turn on automatiedly after a short warm-,lp delay for the amplifier. 3. this point, the instructor need only insert the film into the projector, focus the picture, and adjust sormd levels. The projector stops nr~tomat,icallya t any paint the instructor designat,es by adding n short piece of metallic tape to the film. 4. At any time the inst~xetorwishes to show the a m , he simply pmshes t,he "start" b ~ l t t a nwhich initiates the following ~eqr~enceof event,s.
(a) &nmd is turnedon; 10 sec delay far warm-up. ( b ) Pmjectorstarts. (c) When film is rtmning, depressing the "start" button will reverse projector (with light andsound off). ( d ) Depressing the "start" button again puts the projector in the forwnrdprojection mode. ( e ) At end of film (designated by instructor with strip of metallic tape on the film) the projector rewinds itself automatically.
Classroom Seating
Comfort, good posture, and the availability of an adequate writing surface are all important factors in the design of classroom seating arrangements for effective learning. The following general criteria must be satisfied in classroom design. Good sight lines are essential in rooms where projectors and demonstrations are to be used. To satisfy this requirement in rooms seating forty or more students, sloped or stepped floors must be included in the design of new facilities; if the use of TV and overhead projection devices for displaying demonstrations and instructor's notes are considered, the floors should be sloped sufficiently for all students to see the projection screens. Location oj access aisles should be given more thought; it is possible to locate more seats within the optimum viewing area if access is made from side aisles rather The logic control nit is available from: Summent Engineering, Bozemm, Mont.
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Figure 13. Viewr of the logic controlled projector. o, The proiectar. b, The accessory control boord ir located inride the projector cose and i s activated with o single rwilch. The push button on the remote control cord controls 011 functionr: rtort-stop-reverse. r, The adhesive backed sensing tape 01.0 controlls the functionr of the projedor; tape can b e added or removed without domoge to the film. d, The tope reader (with cover removed).
Recommendalions
It would be desirable to plan several types of conspicuous demonstrations which might bring the merits of an innovative and systematic approach to solving instructional problems, including chemistry facilities planning, to the attention of those responsible for funding new programs. A prototype classroom and laboratory could serve several significant functions. Such a prototype could be visited by teachers and those planning new facilities to see the very latest and best materials in use. Constant service testing, design of new devices, and maintaining channels of communication from the chemical education community to industry would help insure facile communication of appropriate developments. Theprototype Fogwe 14. Seating rtotionr in a suggested chemistry clorrroom design w h t h empharizer talk-back capabilities, facility could also serve as a i n d i ~ i d dresponse stotionr, small TV unih, and omplerpocetorpread out poperr. laboratory where teachers could come to develop their own ideas, drawing on the experience of the project directors; functional specificastudent could have a work space of 16 in. X 24 in. in tions for classrooms and laboratories, motion picture addition to storage space for books under his seat; films, and lecture demonstrations could be developed. a small television set could be shared by two students to view video displays with sharper images (Fig. 14). Conferences for the organized exchange of information In large lecture halls each student could also have a between industry and the academic chemist would be a natural outgrowth of such a project. microphone connected to the public address system; if he has a question, he pushes a "1" button which gives There are many questions which should be evaluated by teachers of chemistry at this time. Some are modern a signal to the instructor and turns on the microphone. The student can then ask questions in a conversational manifestations of questions that have always been present in the methods of perceptive teachers; some voice level which the instructor and the class can hear are becoming increasingly important in the light of clearly (Fig. 14). A versatile student response station could be used moderndevelopments. in conjunction with improved classroom seating. For 1. I s it practical to teach topics, facilitated by teaching aids, 'ystems have not possible in the past, and are these important in the education in which each student has a set of buttons mounted at chemists? .f 2. What is the cost of preparing and maintaining modern his desk. In response to a question from the instructor, teaching hardware, and are the economics involved favorable? one of five alternatives and presses the student 3. What can be done with new teaching aids that cannot be the corresponding response button. The system is donewithoutthem? controlled by the instructor and by pressing a lock 4. Given the capability of modern technology, which projbutton he can obtain a summation of all student ects will be most helpful and practical? answers in analog form displayed on real-time meters; (a) Improved types of opaque projectors so that the color the percentage of students responding to the question, and form of precipitates or the shape of crystals could be as well as the percentage selecting each alternative can shown in the classroom. be obtained. The response information can be preb ) Overhead projectors which combine their present advantages with the "storage" facilities of sliding bards. served automatically in digital form on paper tape by ( e ) Inexpensive Super 8-mm projectors for auditorium use. the instructor pressing a button; the information so ( d ) Individusl film projectors far self-study, or for use in the recorded is summarized with locally produced comlaboratory to replace detailed laboratory manual inputer programs. Syracuse University has several struction. ( e ) Determination of the optimum siee for the "large" lecture programs developed for this purpose. Yale University section, e.g., codd the ideal big classroom be constrocted? has approached the student response station somewhat differently. One of the chemistry lecture rooms uses General Electric (Center for Instruction Communications, 121 foot pedals rather than push buttons since it is felt College Place, Syracuse, N.Y. 13210), Edex Carp. (341 Mofiett students may be less jnhibited when using a 'OnBlvd., Mountain View, Calif. 94041), and Littan Industries (210 cealed signal especially if they do not understand a westch,ter A,,., White plains, N.Y. 10604) $1 offer S L K ~SWgiven point. tems. Volume 45, Number
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( f l The development of lecture experiments where students perform investigations at their classroom desks. (g) The use of audio devices for individualized instruction. Conclusions
we have just begun to see how the new developments in the audio-visual industry can be used to enrich instruction in chemistry by providing more efficient
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uses of films. brinnine. comuuters in the classroom. and providing mkans for preseiting lecture experiments not uossible before. It seems amarent that we must set in motion the same kind of exploration and communication in this area of chemistry instruction which in the more traditional areas has been carried on so effectively over the 44 years of its existence. in THIS JOURNAL
