AV AIDS

 AV AIDS

Audio visual aids are anything by means of which learning process may be encouraged or carried on through the sense of hearing or sense of sight. - Goods, Dictionary of education.

Audio-Visual Aids are those devices by the use of which communications of ideas between persons and groups in various teaching and training situations is helped. These are also termed as multi sensory materials. -Edgar Dale

Audio visual aids are any device which can be used to make the learning experience more concrete, more realistic and more dynamic” -KINDAR S JAMES

Audio-Visual Aids are those sensory objects or images which initiate or stimulate and reinforce learning. – BURTON

Values of AV-Aids

Best motivators: Clear images, Variety, Opportunities to handle and manipulate, Receptivity,  Helpful in attracting attention, Helpful in fixing up new learning,  Saving of energy and time, Vividness, Meeting individual difference

Values: Encouragement to healthy class room interaction, Spread on education on a mass scale, Promotion of scientific temper, Development of higher faculties, Reinforcement to learners, Positive transfer of learning and training, Positive environment for creative discipline

Characteristics: They should be meaningful and purposeful, They should be accurate in every aspect, They should be simple, They should be cheap, They should be up to date, They should be easily portable, They should be according to the mental level of students, They should be motivate the learners, They should be large enough to be properly seen by the students for whom they are meant, They should be improvised.

Classification of A.V aids

(1).Projected aids (2) Non- projected aids.

Projected aids: • Opaque projectors • Slides • Film strips • Overhead projectors • LCD panels • Slide projector (magic lantern) • Epidiascope • Slide cum film strip projector • Films (video materials)

Advantages:

 Provides greater enjoyment in learning, Stimulates more rapid learning, Increases retention: larger percentages and longer retention, Compels attention, Enlarges or reduces actual size of objects. Brings distant past and the present into the classroom, The mental reaction of the pupils to audio-visual experience is both intellectual and emotional.86 % of our sense knowledge is attained through seeing and hearing and hence is the use of audio-visual aids, A-V Aids provide firsthand experience to the children and hence the learning becomes interesting real and durable. A-V Aids help the learner to grasp quickly and retain the experience so received longer; they make a lasting impression on the minds of the learners. “One picture is worth a thousand words” they make learning – realistic, – permanent, – natural and – easy.

Functions of projected aids:

Projected aids supply a concrete basis for conceptual thinking and hence, reduce meaningless word response of students. They have high degree of interest for students. They make learning more permanent. They offer a reality of experience which stimulates self activity on the part of pupil. Develop continuity of thought; this is especially true of motion pictures. They provide experience not easily obtained through other materials and contribute to the efficiency, depth, and variety of learning.

Need and importance of projected aids:

Projected aids motivate student’s mental and physical activity. Save time. Provide firsthand experience by looking at concrete things, living specimen, handling apparatus and actual demonstration etc. Pupils to have clear conception of ideas, information, facts and principles. Help to bring a change in the atmosphere of the class. Provide a congenial atmosphere in the class. Help to develop scientific attitude and get training in scientific method. Large number of students can taught at a time. Most convenient, easy and natural way of learning. Make learning effective and durable.

Types of projected aids:

Opaque Projector: A device which displays opaque materials by shining a bright lamp onto the object .A system of mirrors, prisms and/or imaging lenses is used to focus an image of the material onto a viewing screen. Opaque projectors require brighter bulbs, larger lenses. Care to be taken to prevent material damage, Not very common. Consists of two mirrors at top. Light rays passes through the first mirror, then to the object, light rays from the illuminated picture then focuses to the second mirror , then it is projected to screen by using a convex lens, then the picture want to project is placed on the plate and handle is fixed again , then switch on light 1000watt  bulb.

SLIDES:  A slide is a still transparency of 70mm, 35mm or 6mm size which is optically enlarged and projected on a screen as a real image. Some kinds of slides are, Marker slides Cellophane slides .Silhouette slides, Etched glass slides.

Advantages: They attract attention, they arouse interest, they assist lesson and development they test student understanding, they review instruction they facilitate teacher student participation.

Disadvantages:  More time consumes for preparations of slides, They can only be seen with the help of slide projectors, Students can’t see the slides with the naked eyes, Expensive material is used for making the slides, Many errors occurs during preparation.

Film strip: A filmstrip is one of the projective audio visual that a fixed sequence related still on a roll of 35 mm film. The filmstrip can be projected backside of the map as convenience of the teaching situation demand. A large number of subjects come within the range of filmstrips. The teacher only needs to tap the right type of strip for his teaching purpose. Show the slide and explain, Insert the next slide. Present the slides or frames sequentially, switch off the bulb first then the cooling fan, unplug the slide projector and store it back in its box.

Advantages: economical, easy to make, convenient to handle, Takes up little, can be easily stored, Provides logical sequence, Can use AC/DC power, batteries, or rechargeable batteries with solar panels.

Disadvantages:  Need a darkened room. Require equipment and power that will need to be maintained. Sequence cannot be changed. Visual media only; it requires audio or printed text. Require professional assistance for final production.

Overhead projector: An OHP is an important electronic teaching aid. This machine projects an image from a transparency It will be advisable to switch off the bulbs of OHP for 5 minutes after every 10 minutes of use.

Advantages: teacher can face the class without any difficulty. The teacher can maintain eye contact and observe the reactions of students. Small objects can be shown on the machine simply by placing them on projection slide. The graphics and writings can be shown very clearly and colorfully. It does not need as darkened room as compared to other projectors

Slide projector:  It is used to project slides.  Used for projecting pictures from a transparent slide on a wall or screen. It helps in showing the magnified image of the slide. If the slide is colored it would be more attractive.

Construction of slide projector: Source of light (projection lamp), Reflector (concave mirror), Condensing lens, Slide carrier, Objective lens.

Working:  When a figure or illustration is very small and it is required that whole class should see it clearly, a transparent slide of small figure is prepared. Slide is placed inverted into the slide carrier part of the projector. The light rays emitted by the source of light and reflected by the concave mirror lying behind the lamp, are directed forward to fall on the condensed lens. Advantages:  Arouse attention and interest of the students’ .Variety of educational information can be given. Easy to transport, Easy to use, Economical in time, not costly, Non – fragile, non- inflammable.

Disadvantages: Not suitable for all types of educational material. Transparent slides can’t be put to excessive use. Not to use for longer duration.

Video materials:  The video cassette recorder helps to enhance the educational and entertainment values of the television. The video lessons are more effective than the conventional lessons and serve as a better models as they are given by more efficient teachers. Precautions while Using Videotapes, Preview the videotape .Check to be sure that the videotape is compatible with the videotape player, Cue the videotape to the beginning of the program arrange the room so that all participants can see

Advantages: Source of entertainment. Source of information .Stimuli for discussion. Animation can be used to show an abstract concept. TV monitors tolerate fluctuations in voltage much better than projectors. Video players are less expensive and easier to maintain than slide projectors.

Disadvantages: commercially prepared videotapes are often outdated .Videotapes may have been edited and omit or rearrange key training steps in the procedure. Participants may be distracted by cultural differences.

Non- projected aids:  Cartoons • Charts • Comics • Diagrams • Flash cards • Graphs • Maps • Photographs • Pictures • Posters • Printed material • Black board • Bulletin board • Flannel board • Magnetic board • Diagrams • Models • Puppets • Specimens.

Cartoons:  Humorous caricature which gives a subtle message, Preparatory drawing for a piece of art such as painting

Charts:  Visual symbols Used for summarizing, comparing, contrasting etc. Combination of pictorial, graphic, numerical or vertical material which present a summary.

Types of charts: Narrative Charts: Arrangement of facts and ideas to express the events in process of development or improvement. The chain chart: Arrangement of facts and ides to for expressing a cycle. Evolution Chart: Arrangement of facts and idea to express the change from binging to future.  Flow Chart: Used to show organizational elements or functional relationship using lines, boxes, circles etc. Flip charts: A series of charts on a topic tagged together on a sporting stand. It conveys a message in a sequence.  Pie Chart: A circle with different sections having a key mentioned with chart is used to differentiate, compare or to show any relationship between different entries. Flash cards: Set of pictured cards of varying sizes. Flashed one by one in an order.

Comic strip: Graphic representation in a series of pictures or sketches, Full of action.

 Graphs:  Represents statistical data, Contrasting the trends or changes of certain attributes.  Types: Bar Graph: the graphical representation extends the scale along the length of bar. These graphs are in two forms; horizontally and vertically. Line Graph: Used to show the trends and relationships through lines. Pictorial Graph: Pictures are used to illustrate any idea, observation or measurement, graphically. Pie Graph: A circle diagram in which data is presented through sections or portions.

Maps:  Represents the proportionality as a diagram, the surface of the earth, world or parts thereof.  Conveys the message by lines, symbols, words and colors.

 Types:  Political Maps .Physical Maps. Relief Maps. Weather Maps. Population Maps. Tourist Maps.  Road Maps. Railway Maps. Air Maps. Sea Root Maps.

Puppets: Manipulates doll dressed as a character and the performer is a person termed as a puppeteer. Used in language teaching and social sciences.

Types: String Puppets, Stick Puppets, Shadow Puppets, Finger of Hand Puppets.

Display boards: Used to display news alerts and information for a specific group of individuals.

Types: Chalk board, White Board, Flannel Board, Bulletin Board, Peg Board, and Magnetic Board.

Models: Recognizable representation of a real thing three dimensionally, Height, width, depth is felt as reality.

Types: Solid Models, Cut-way and x-ray models, working models, Sand models.

Developing Instructional Materials:

Develop instructional material based on a given instructional strategy: Given an instructional strategy, describe the procedures for developing instructional materials. Name appropriate rough draft materials for various final media. Describe the designer’s role in materials development and instructional delivery. List four categories of criteria for judging the appropriateness of existing instructional materials. Name and describe the components of an instructional package. Describe factors that may cause revisions in media selections and delivery systems for given instruction. Objectives.

All instructional material should be accompanied by objective tests or by product or performance assessments. These may include a pretest and/or a posttest. Assessments, used by the instructor or course manager. Special attention should be paid to the ease with which course management information can be a variety of communication and messaging mechanisms ,grade book ,project monitoring ,online testing ,student tracking ,automated class listing, student guidance templates tests and other information considered important for implementing the course.

The materials may also include information that the learners will use to guide their progress through the instruction.nstructional materials refer to any preexisting materials that are being incorporated, as well as to those that will be specifically developed for the objectives.