Audio-visual aids – Sensitive tools used in teaching

Dr. V.K.Maheshwari, M.A. (Socio, Phil) B.Sc. M. Ed, Ph.D.

Former Principal, K.L.D.A.V.(P.G) College, Roorkee, India

Mrs Sudha Rani Maheshwari, M.Sc (Zoology), B.Ed.

Former Principal. A.K.P.I.College, Roorkee, India

A Chinese proverbs  says “If I hear I forget, if I see I remember, if I do I know” emphasizes the importance of sensory perception of teaching, learning situations. Audio-visual aids are sensitive tools used in teaching and as avenues for learning; these are planned educational materials that appeal to the senses of the people and quickens learning facilities for clear comprehension.

An audio-visual aids is an instructional device in which message can be heard as well as seen.

“Audio visual aids are any device which can be used to make the learning more effective, more concrete, more realistic and more dynamic.”Kinder

“Audio-visual aids are those aids which help in completing the triangular process of learning.ie, Motivation, classification, stimulation”. Carter.v.Good

Audio-visual is, of course, a combination of two words: audio referring to that which we can hear, and visual referring to that which we can see. The basic frame of reference here limits our application of the term to a instructor and his audience, although they are not necessarily in the physical presence of one another, as in the case of a motion picture or television presentation.

The term “aids,” used in reference to the instructor , rules out his physical presence (visual) and unrecorded voice (audio). These are the essential elements which make him a instructor , and therefore cannot aid him.

Audio-Visual Aids

The term “audio-visual aids” is commonly misapplied. The aids themselves must be something either audible or visual, or both. The common types of audible aids are the spoken word, recognizable sound effects, and music. The most frequently used visual aids are people, pictures, cartoons, graphics, maps, the printed word, and three-dimensional models. When we talk about a motion picture projector or a blackboard, we are talking about the means of presenting the aids, and not the aids themselves.

First and foremost, a program should be undertaken simply and modestly. It is better to leave the expensive technical gadgets and special effects to the future. Start with one piece of equipment and master its use. Add the various attachments, or go on to another piece of equipment, as needs dictate.

Further, the uncontrollable physical surroundings are not audio-visual aids in themselves, although they can have a definite audio or visual effect and should therefore be considered, if possible, when preparing a presentation. These include such things as distracting street noises (a hindrance) or a soundproofed room (an aid); or a beautiful mural behind the speaker (a distraction), purple and orange walls (a hindrance), or a paneled, modern meeting room with indirect lighting (an aid).

The mixing of various pieces of equipment in a presentation can be extremely effective. Some examples have been mentioned, and serious consideration should be given to the possibilities. The problems of light and dark rooms must be considered, so that the transition can be made smoothly from one item to another.

Audio-visual materials can be divided into those which present the aids in their original form, and those which reproduce the original form.

A.V aids provide a basis for more effective perceptual and conceptual learning. They   initiate and sustain attention, concentration  and personal involvement of the students in learning, as they provide concreteness, realism, and life likeness in the teaching-learning situation. A.V.aids bring the remote events of either space or time into the class room , thus bring the meaningfulness  of abstract concepts. A.V aids helps to gain practical skills and to introduce opportunity for situational or field types of learning as contrasted with linear-order verbal and written communications .The students acquires clear, accurate and vivid image during the process of learning. A.V aids stimulate curiosity and concentration. Stimulate thinking and motivation. Help to develop thinking process as they develop continuity or thought. Students develop higher faculties among the students and it promotes memorization, thinking process and reasoning power.

Principles for selection of Teaching Aids

The selection of suitable teaching aids is very important for the for the success of the learning process .Unsuitable selection can result in more harm than good, because it can cause confusion in the minds of the students being unrelated.

A teacher should keep in view the following principles while selection suitable teaching aids:

1. 1. Principle of selection: The selected teaching aids should have the basic traits .It should be definitely important from educational viewpoints. It should be interesting and should be able to motivate students for learning. It should encourage the achievement of instructional objectives.
2. 2. Principle of Preparation: A teacher should devote himself and make students ready to the teaching aids psychologically. He himself should know about the nature of the selected teaching aids. Before demonstrating the class, he himself should inspect the teaching aids in all its respect.
3. 3. Principle of Proper Presentation: He should ensure that both subject matter and teaching aids are properly coordinated and related. Teaching aids should be used as supplementary aids. A teacher should be fully proficient in its use.
4. 4. Principle of Control: The teaching aids should be under the control of the teacher during the entire period. No such situation should be allowed in which a teacher is not able to control and use the teaching and properly.

Audio visual room:

It is always worthwhile to have a separate audio visual room in the school. The room should be planned to facilitate the optimum use of audio visual aids. An audio visual room should be spacious enough to accommodate about sixty students at a time.

Main factors:

• Acoustics- for proper acoustics, the wall must have straw boards and window heavy curtains.
• Lighting- The lights of the room should have facility of controlling these from a single switch to darken the room for projection.
• Wall sockets- Wall sockets should be easily accessible to plug in the audio c=visual equipment.
• Ventilation- a proper ventilation of the audio visual room should be provided with a few exhaust fans.
• Storage- for storing the audio visual material, wall cupboards and racks should be used.
• Seating- the seating arrangements using movable chairs should be done so that the students are seated in a sector of sixty degree from the center of the screen.
• Other- audio visual material for display should include chalk board, display cases, display boards, graphs, show windows, shelves.

CLASSIFICATION OF AUDIO-VISUAL AIDS

Auditory Aids                                             Traditional	Audio Visual Aids	Aid through
Media		Activity
(Radio recording,                                                             (Puppets,Microphone)	(Television, Drama)	(Field trip, Exhibition)

 

Projected	Non Projected
(OHP, Slide projector, Magic Lantern, LCD,                          Projector, Still and Motion picture Projector)	(Charts, Flannel, Graphs, Black & White Board, Cartoons, Maps, Posters, Printed materials)

 

Non Projected Aids:

Graphic Aids	Display Board	3D Aids
Cartoons Charts Comics Diagrams Objects Flash Cards Specimens •             Maps •             Photographs •             Pictures •             Posters •             Printed materials	Black Board Bulletin Board - Flannel Board - Magnetic Board - PEG Board	* Diagrams Models * Mock Ups Puppets

 

Graphical aids:

Cartoons:

A cartoon is a form of two-dimensional illustrated visual art. While the specific definition has changed over time, modern usage refers to a typically non-realistic or sem-realistic drawing or painting intended for satire, caricature, or humor, or to the artistic style of such works. A simple drawing showing the features of its subjects in a humorously exaggerated way, especially a satirical one in a newspaper or magazine:

It is the metaphorical presentation of reality. It makes the learning more interesting and effective as it creates a strong appeal to emotions. It uses symbols to portray an opinion, a scene, or a situation.

A cartoon is a humorous caricature which gives a subtle message. In a cartoon, the features of objects and people are exaggerated along with generally recognized symbols. In short, a cartoon is a figurative and sub tile graphic aid. A cartoon has an instantaneous visual and a tickling message.

Many times, Cartoons in newspapers can be sarcastic and ridiculing. The main sources of cartoons are periodicals. Newspaper carry cartoon which are either political or social in nature. Special periodicals and magazines carry cartoons on science, management, economics and education.

If a teacher is resourceful he/she can convert certain ideas into cartoons with little practice. Nevertheless, he can clip the cartoons from the periodicals and mount them for classroom.

The cartoon makes use of ,personalized humor, fantasy, incongruity, satire and exaggeration.

Advantages:

1)      Cartoon can be effectively used to initiate certain lesson.

2)      Used to motivate students to start discussion

3)      Can be used for making lessons lively and interesting.

Disadvantage:

1)      While using cartoons as instructional aides,  if  the teacher do not  choose them judiciously and discriminately  can injure personal feelings or social group.

Charts:

A chart is a graphical representation of data, in which “the data is represented by symbols.

Charts are often used to ease understanding of large quantities of data and the relationships between parts of the data. Charts can usually be read more quickly than the raw data that they are produced from. They are used in a wide variety of fields, and can be created by hand (often on graph paper) or by computer using a charting application. Chart is the graphic teaching material including diagrams, posters, maps, and graphics which presents a clear visual summery.

Purposes of Charts:

• Showing relationships by means of facts and figures.
• For presenting the material symbolically
• To show continuity in process
• For presenting abstract ideas in visual form
• For showing development of structure
• For creating problems and stimulating thinking

Types of charts:

 

TYPE	WHAT ASPECT
Tree Chart	A chart made in form of branches from the trunk of a tree such that represents the main idea while the branches represents various development, relationship of sub parts of the main ideas. E.g.: family tree
Stream Chart	It is a graphic aid showing the main thought, idea, concept in the form of a main river and it sub parts in the form of tributaries coming out of it. E.g. free hand drawing
Table	Table charts are very valuable aid in teaching situation to show comparison, distinctions and constant between two or more things. Its size is 50×75 cm or <. It should caption in bold letters, with different features in different colors. E.g. numerical data, descriptive observations.
Flow Chart	It is a graphic aid of system requiring presentation in the form of connected lower divisions of the system in boxes and line to show their relative positions with respect to the higher position in the system. E.g. organizational chart.

COMICS:

WHAT	ARGUMENTS-IN FAVOUR:	ARGUMENTS AGAINST
A comic strip is the graphic depiction in a series of pictures or sketches of some characters and events full of actions. A large number of comic strips depicting long continuous episodes are published in book forms.	1.Comic strips fire the imagination of the children. 2.Comic strip boosts the courage of children and builds up the spirit of adventure. 3.Comic strips make communication detailed and vivid. 4.Comic strip stimulates reality and thus involvement.	1.Comic strip misguides the children by depicting characters with supernatural powers divorced from a hard reality of life. 2.Comic strips hamper the development of language in children. 3.Classics brought out in the form of comics develop the tendency in children to ignore or bypass the original work. 4.Comics soon become obsession with young children and they tend to avoid serious students

 

 

Precaution:

The teacher must use with discrimination and only those related to biographies, social events scientific interventions and historical events should be used selectively for classroom instructions.

Diagrams / Drawing:

It is a simplified drawing designed to show interrelation primarily by means of lines and symbols, e.g. stick figures, geometry drawings, facial expressions. Drawings can be done by hand to convey a variety of ideas, concepts and situations. It can be better used for summery and review.

Standard of a good diagram:

1. Technically correct.
2. Neatly drawn in proper proportion.
3. Well labeled and explained.
4. It can be moved and seen from all angles.

 

Map:

Graphic representation of the earth’s surface or portions of it are termed as maps. These are flat representations of earth’s surface, which convey the information by means of lines, symbols, words and colors.

Various aspects of maps:

• Understanding and interpreting the key of index, tints, shadows and symbols.
• The top every map is not north, but the direction of northern pole is north.

Types of maps

TYPES	WHAT ASPECT
Relief maps	A raised-relief map or terrain model is a three-dimensional representation, usually of terrain. When representing terrain, the elevation dimension is usually exaggerated by a factor between five and ten; this facilitates the visual recognition of terrain feature.
Historical maps	Historical maps are those which represents graphically a succession of events, states, or an act
Distribution maps	A distribution map is a map that uses colors to show information such a population or housing     prices.
Geographical maps	A geographical map is the map which shows geographical landmarks. Flash cards

A flashcard or flash card is a set of cards bearing information, as words or numbers, on either or both sides, used in classroom drills or in private study. One writes a question on a card and an answer overleaf. Flashcards can bear vocabulary, historical dates, formulas or any subject matter that can be learned via a question and answer format. Flashcards are widely used as a learning drill to aid memorization by way of spaced repetition. Due to their small size and effective use in rapid sequences, flash cards are difficult to adapt to a planning situation. They are used primarily in language training, testing, or to emphasize key words or actions.

Illustration made on heavy paper that is usually smaller than 21cm x 27cm. the illustrations are not bound, but are arranged in sequence.

Audience Size:

• 5 to 15 people. Because the illustrations are small, no more than 15 people should be in the audience.

Advantages:

Inexpensive, can be home made from local materials. Good way to present a “changing” message in areas where people gather.

Disadvantages:

If out of doors, weather damage can occur. Constant supply of good educational material to put on the board is needed.

Points to be taken care of:

The set of cards can be prepared on a single topic, put in a sequential manner, before starting the explanation.

• The story on each card must be familiar, in simple words and local terminology.
• Hold the cards at the chest level where people can see clearly, hold it against body and not in air, face different parts of the group to show the cards to all.
• Glance down at cards, as you are ready to explain and make sure to given correct information.
• Use pointer. Do not cover the matter with hands. Be enthusiastic and enjoy explaining.
• Important point should be written backside.

Flip Charts:

A series of visual aids on flexible paper, fastened together at the top and mounted on a frame in such a manner that they can be flipped or folded back. The frame usually resembles a football goal post, with the charts fastened to the crosspiece.Illustration made on paper that is usually larger than 21cm*27cm; bounded together with rings or string. They flip over in sequence.

Audience Size:

• 15 to 30 people. It depends on the size of the flip chart too.

Advantages:

• Inexpensive, can be home made, and can be easily transported. Good way to give information in sequence; because they are bound, illustration stay in sequence.

Disadvantage:

• Deteriorate with constant use. Some artistic ability required if making homemade flip charts.

Preparation:

• The first card of bunch should be giving brief introduction of the topic.
• 8 to 12 cards can be used in bunch.
• Each card should show a picture illustration in front side, conveying one idea at a time.
• The brief description or explanation of card number 2 should be written at the backside of card one, which can be seen by the teacher if she forgets.
• The picture used should be adopted to local condition and should be colorful.
• Leave enough borders so that it doesn’t cover the matter with the hand while holding.
• Use pointer while explaining details of picture on card.

Graphs:

Graph is a visual teaching aid for presenting statistical information and contrasting the trend or changes of certain attributes. Diagrammatic representation of numbers, takes several common forms. Pictures are sometimes used, particularly in bar and flow charts.

Types of graphs:

TYPES	WHAT ASPECT
Pictorial graph	It is an outstanding method of graphical representation. Pictures are used for expression of ideas; they are more attractive and easily understood. Vivid pictures will be used to create rapid association with graphic message; each visual symbol used to indicate quantity.
Bar graph	It consists of bars arrange horizontally or vertically from an origin base. It is useful in comparing and contrasting two variables or two groups
Pie graph	it is usually shown on a disk (pie) or a circle divided into sectors of different angles to represent fractions or percentage of the division of a distributive nature Pictures and photographs:

Pictures are the most commonly available graphic aids. Picture includes photographs, paintings etc.

Effective use of pictures:

• The picture can be flashed in front of the class & related questioned asked to initiate the sections.
• A series of pictures related to the lesson can be displayed in the classroom to arouse the curiosity and interest before the lesson begins.
• The picture should be large enough for the whole class to see it properly.
• The picture must have clear details for arresting attention and interest.
• The pictures should be related to lesson and meaningful to students.
• The picture should be authentic and identifiable.
• The picture should be able to build up proper learning environment.
• The picture must lead the class to some purposeful activity.

Posters:

A message on a large sheet of paper, with an illustration and a simple written message on it.

Standard size is 20”30”.

Audience Size:

No limit, because it is not necessary for everyone to look at the poster at the same time.

Advantage:

• Inexpensive, easy to make.
• Require a minimum amount of time to prepare and use.
• Easy to transport

Disadvantage:

• Demonstrate rapidly
• Can confuse the audience with too much or too little information.
• Need some artistically ability if making own posters.

Uses:

• Advertising an event or product.
• To make instant appeal.
• To convey a single idea or few ideas.
• Giving a direction or warning.
• Suitable or client education, presenting scientific facts, showing safety measures and many other facets relating to health for propaganda, popularizing symbol or sign.
• Simplicity, short message, colorfulness and eye catching figurative design are features of good posters.

Chalk board:

Black, green or other colored slate or composition board, or a specially painted surface which will “take” erasable white or colored chalk.A rigid surface painted green or black, on which one can write or draw with chalk.

Audience Size:

• 10 to 30 people. If used with more, a large board is needed and careful audience placement is necessary.

Advantage:

Inexpensive, can be home made, easily maintained, minimum preparation.

Disadvantage:

• Transport can be difficult in remote areas. Limited to users artistic ability.

Points for effective black board work:

• The black board must be easily visible.
• Must have a matt surface and free from glare.
• It should be in good light so that work is seen without strain.
• The teacher should not stand in between pupil and blackboard.
• Letters and figures must be large.

Bulletin Boards:

A bulletin board is essential when illustrations have been prepared on thin, flexible paper. It is usually helpful to have an assistant do the mounting, or the planner will have to turn his back to the audience and fumble with the material. A blackboard can be considered a bulletin board, with the aids mounted with tape rather than pins or tacks. It might be noted here that small visual aids can be enlarged by a photostatic process, at relatively small cost, for presentation on a bulletin board.

It is a surface of at least 1.5 meters. Into which stick pins can be placed. Drawings, photos and lettering can be displayed on board.

Audience Size:

No limit because it is not necessary for everyone to look at the same time.

Advantage:

• Excellent way to use actual materials in a real situation.
• Uses local materials.
• Easy to understand by people not used to look at illustrations.
• Good way to get audience participation.

Disadvantage:

• Takes lot of preplanning an d preparation.

Flannel board:

A piece of flannel, flannelette, terry cloth or felt cloth attached to a rigid surface on which cut out figures will adhere if backed with flannel or felt cloth, sand paper or glued sand. Standard size 1.5 meters.

Audience Size:

• 15 to 20 people. Audience size depends on the flannel board.

Advantage:

• Inexpensive, easily made from local materials. Easily maintained and transported in remote areas. Figures can be used in different presentations. Figures can be used in different presentation.
• Ideal for showing “sequence of events” and reviewing lesson, as figures can be brought back on board.

Disadvantage:

• Requires considerable advance preparation.
• Difficult to use outside.
• Some artistical ability is required if making homemade figures.

Uses:

• Collect the pictures light objects or make cutouts & back them with sand paper pieces.
• Display material on the flannel board in a sequence to develop the lesson plan.
• Change the picture or cutout as you talk to the client.
• Use the flannel board to create proper scenes 7 design relevant to the lessons.
• Flannel boards can be used to tell a story, interrelationship with different parts or steps of process.

Projected Aids:

Film or motion pictures:

Color or black and white, 16 or 18mm cinema film, with sound projected on screen. A long, narrow strip of cellulose nitrate, acetate or similar material containing a succession of small transparent photographs. Common sizes are 8 and 16 millimeter, referring to the width of the strip.

Audience size:

• 30 to 100 people. Group can be larger than 100, but it is difficult to have discussion in larger group.

Advantage:

• A film has movement. It can show processes, methods and procedures.
• It is three dimensional in its impact.
• It can create the impression of space and time.
• The technique of caricature & animation makes it possible to give meaning to abstract notions and scientific theories
• The sound track of film lends realism to the visual image in the form of genuine sound impressions.
• It admits the voice of experts, the performance of the specialist & aids atmosphere, mood and understanding.

Disadvantage:

• There is complete exclusion of teacher from presentation.
• The machinery of presentation is cumbersome and not easily adapted to average classroom.
• Expensive in terms of preparation and projection.

Film strips:

A filmstrip is usually compiled from a number of individual pictures taken with a 35 mm. still camera.Film Strip is mostly 35mm film, color or black & white photographs in sequential order. Film strip projected on screen or on a wall. They use projector with film strip adapter. Film strips are in horizontal or vertical format.

Audience Size:

• About 30 people. Though film strips can be used with more people, the educator can stimulate better discussion with group of this size.

Advantage:

• Dramatize & get the audience attention. Show motion and thus helps to explain step by step and time sequence very well.

Disadvantage:

• Very expensive, requires expensive equipment, electricity and dark projection area. Difficult to transport and operate.

The Epidiascope (Opaque projector):

An Epidiascope projector, projects the image of a solid object. It often referred to as an opaque projector. The principle is “bright light is concentrated upon an opaque object and the brilliantly illuminated image is reflected by a mirror through a very large lens on to a screen”. An epidiascope can project a wide variety of material and makes the teacher dependent of standard transparent material.

Epidiascope can project:

• Flat pictures
• Post cards and photographs
• News items and illustrations
• Book illustrations
• Tables of statistics
• Handwork diagrams
• Pupil’s  work
• Solid objects- watches, coins, nature study samples and geological specimens, maps.

Advantages:

• Epidiascope has the ability to compel attention.
• It keeps the initiative of selection of material, and pace of presentation in the teacher’s hand.
• The preparation of material is simple and its preview for the purposes of lesson preparation presents no difficulty.
• The nature of material makes additions, amendments, alter action and substitution easy.
• Material can always be up to date.

Overhead Projector:

The OHP is a versatile visual aid using a system of lens, mirror and lamp, transparencies are projected on to screen in a way that enables teacher to face the student while teaching.

Advantage:

• Teacher can make eye contact while teaching.
• The OHP can be used in day light allowing the students to take notes, only bright light near the screen needs to be switched off.
• Prepared can be reused saving time during class.
• OHP is user friendly.

Disadvantage:

• Keystone effect-projected material is wider at top than at bottom.
• OHP bulbs are expensive.

Guidelines for making OHP transparencies:

• Check display area of OHP and select transparency size accordingly.
• Leave margin of ½ inch to ¾ inch free on all sides.
• Plan layout of transparency. Phrases, key points not long sentences.
• Use 6-8 words in a line.
• Use lettering 2/5 inch for small group. Minimum ½ inch for large group. Use more lower case letters than upper case letters.
• Use dark colors.
• Framing is useful for (1) to attach flaps for masking. (2) to attach transparency layers.

Slides:

35mm film in plastic or cardboard mount 5cm*5cm. in color or black & white. They are projected on a screen or walls.

Audience size:

• About 30 people, though slides can be used with more people, the educator can stimulate better discussion among a smaller group.

Advantage:

• Dramatically less expensive than cinema film and slides once inserted in the projector, impossible to get out of the sequence. Can show photos of the real thing and show sequence in time. Battery operated projectors available. Relatively easy to transport.

Disadvantage:

• Requires projection equipment, can be damaged, and requires either mains or battery to operate.
• Sometimes batteries are expensive. Requires darkened projection area. Limited appropriate slides are available.

Preparation of slides:

• Collect all available slides check them against a lighted lamp. Choose the slide relevant to your lesson.
• Arrange them in sequence and write a brief introductory note for each slide on a card.
• Create a dark environment, arrange screen and other facility. Adjust objective lens for proper focus.
• Make proper seating arrangements for the students within an area covering a sector of 60 degrees from center odf the screen

Three dimensional aids: