Types of Instructional Materials
Communication and consequently teaching is more effective when more than one sense is used. The teacher who relies only on the spoken word to deliver the message is less effective than one who uses several senses (a multisensory approach).
One sure means by which the teacher attempts making the contents an communication understandable to the learner is the use of instructional materials. Instructional materials are go-in-between channel through w hich information is disseminated from the teacher to the learner.
They are classified in different manners. The y come in a form of audio, visual, audiovisual, projected, non-projected, hardware, software, specimen, realia/real objects, etc. Attempts shall be made to explain some of them in details. A multi-sensory approach improves reten tion (the ability to rememb er), which is vital in education.
The commonest instructional materials are audio-visual ones where the teacher combines the senses of seeing and hearing. These can be classified into projected and non-projected aids.
Projected aids include the overhead transparency (projector), kaleidoscopes, films, video cassettes and slides. They are powerful aids if you can obtain appropriate ones, but they are expensive and difficult to maintain. The overhead projector is relatively cheap and easy to maintain and is easily available.
It will be described here in detail to enhance its use in training institutions.The overhead projector
The overhead projector (OHP) projects large transparencies from a horizontal table via a prism or mirror and lens. A bright image appears on a screen behind the teacher.
Setting up your projector screen
The setting up of the screen depends on:
• The type of room
• The size of the audience
There are two possibilities of projection:
• Project behind
• Project slightly to the side (better viewing) When lecturing, stand to right or left of the projector.
How to prepare transparencies
When preparing transparencies do not write too close to the edge–you might loose half the image. Leave at least an inch of margin all round.
• For more complex drawings, prepare a pencil sketch then lay the transparency over the sketch and cop y onto the transparency. You can also copy a diagram from a book.
• Lettering should not be too small – about 4mm (one-eighth of an inch).
• A transparency should convey one theme. Put as much as necessary but as little as possible on a transparency. Ensure clarity and impact.
• Leave room for future alterations.
• Jot down your lecture notes on the frame of the OHP.
• Keep content down to 10 lines with 10 words on a line.
• When masking, use thin paper – the lecturer will see the whole transparency but the audience will see only the information which has been revealed.
• Overlays: do not use more than six build-ups – brightness will be impaired.
• Store your transparencies with care. Avoid moisture and dirt.
Advantages of using OHP
• The teacher faces the classroom and can point out features appearing on the screen by pointing to the material.
• Darkening of the room is not necessary.
• A wide variety of materials can be projected.
• Transparencies can be used as an illuminated blackboard during the class period or transparencies can be prepared beforehand.
A number of transparencies can be put on top of each other showing stages of develop ment, e.g. of an idea or structure.
Tracing of diagrams and drawings is easy.
• Transparencies can be made in many colours, both permanent
and non-permanent depending on the pens and ink used.
• The overhead projector has endless possibilities in the hands of a resourceful teacher and has applications at all levels of education.
Disadvantages of using the OHP
• The teacher must not stand in front of the image.
• Acetate sheets are difficult to obtain, but spoiled and cleaned X-ray film is a useful alternative.
Technique: A low-qualit y X-ray film still wet, is kept in water f or one or two weeks. The emulsion layer can then be stripped off. (When the film has dried it will take a much longer time for the emulsion layer to come off). The result is a transparent, slightly bluish sheet which can be used in the same way as transparent acetate sheets.
• Special felt pens are used for writing on the transparent sheets. If they are difficult to obtain, the glass pencils used in laboratories are a substitute. Erase with water (or with spirit for semi-permanent ink).
Care and maintenance
• After finishing a demon stration do not remove the wire plug from the socket but switch off the lamp and keep the fan running until the bulb has cooled down (there is a thermostat fitted in most types of OHP).
• Keep lenses and mirrors free of dirt.
• Keep a spare bulb in stock.
• Store semi-permanent transparencies together with master copies of handouts in a file with the unit block or subject concerned, so it can be found easily when needed and used again the following year.
These include the chalkboard, pictures/cartoons, flipcharts, posters, “the real thing”, handouts and flannel boards.
The chalkboard is the most convenient and most used teaching aid. However, it is often badly used. As with all teaching aids, it requires planning in order to achieve effective learning. In planning how to use the board, teachers should ask themselves the following questions:
• Which parts of the lecture are important enough to be written on the board?
• Which aspects of the lecture are likely to be unclear?
• Which diagrams and/or drawings can be used to explain difficult points?
• What are the main points or steps in the lecture?
• Will the use of the chalkboard save lecture time? Do you need to use the chalkboard before the students assemble or is it possible to use a less time-consuming aid, e.g. slides or the OHP?
Some common faults in using the chalkboard
The chalkboard is used as an exercise book. Every word the teacher says is written down. This is time-consuming and does not discriminate between essentials and examples.
The chalkboard is used as scrap paper: The teacher’s writing is too small, untidy or otherwise illegible. The board is filled with letters, symbols and figures all fighting for attention.
A lecture is delivered to the chalkboard instead of to the students: A teacher working at the board should face it at an angle so that he/she can also look at the class frequently. The teacher should not cover the work on the board so that all students can see what he/she is writing down.
Some aids to chalkboard work
Templates: Shapes cut out of card or plywood help to outline figures which are often needed, e.g. a triangle in mathematics.
Bounce pattern: A sheet of thick rough paper in which a certain outli ne e.g. a map of a country with its region, is punched out along the outline. The paper is held against the chalkboard and a chalky duster flicked along the line of perforation.
When the paper is taken away, lines of dots appear which can be joined by the teacher to produce the wanted drawing. Semi-permanent lines: Such lines can be produced by using soft chalk soaked in sugar solution. They can be wiped off with a damp cloth.
Slides, photographs, picture-drawings, line-drawings, cartoons etc., are good teaching aids. Good and appropriate pictures are difficult to obtain or prepare.
Flip charts as an instructional medium is so called/named because of its potential feature of accommodating more than a chart. This is good to illustrate processes in a “flowing” form.
These are cheap and easy aids to prepare. They can be made from butcher paper, old calendars, paper boxes, manila paper, etc. The diagrams can be drawn by somebody else or traced on. The pictures should be labelled in legible handwriting.
When labelling, remember to:
• Use thick felt pens.
• Use different colours for emphasis.
• Write in upper and lower (small) cases letters not capitals.
• Do not write too much.
When making a presentation using flipcharts, do not read the chart as you talk. The secret is to make some no tes at the back of the flipchart to guide your discussion. Always face th e audience.
Posters take longer time to prepare than flipcharts. They may consist of words only, pictures only, or a mixture of both. Unlike flipcharts, posters are usually single-leafed. Posters need a lot of planning and testing before use. They can be prepared for two types of viewers:
– For a mixed (heterogeneous) audience e.g. on a street for the general public.
– For a captive audience e.g. in a class.
When a poster is being prepared for a heterogeneous audience, it should deliver the message at a glance. When preparing a poster, remember the following:
• Make it simple
• Use simple language – avoid difficult word s or slang
• Put as little as possible on the poster.
The Real Thing (Realia)
The best teaching aid is “the real thing”. For instance, it is much better to teach mothers how to wash a baby by using a real baby rather than a doll. A live baby cries and kicks, a doll does not. These characteristics have to be taken into account in teaching mothers how to wash a baby.So try as much as possible to use “the real thing” in your lessons.
Your first thought should be: is it possible for me to demonstrate the real thing to my class in this lesson? Only when this is not possible should you think of other teaching aids, that are im itations to the real thing. The closer the imitation to the real thing, the better the teaching aid.
This is an important consideration in helping the learner to transfer the impression he gets from the lesson to the real thing. Teaching aids that are seen in the places where they belong are easier to understand and remember. A field trip is the general term for taking a class to the “real thing” in its context or normal surroundings.
The Flannel Board
This is the device of choice for teaching in rural areas. All rural-health educators should know how to use it. The operation is based on the fact that materials with rough surfaces tend to adhere to each other. If flannel is not available, alternative materials can be found.
The board is put in front of the class, sloping slightly backwards. Cards with a rough backing (e.g. sand paper) can now be placed on the board in any position. The cards can be moved or taken down at wills. Make cards from large print or written words, e.g. newspaper cuttings, photographs or dissected posters.
• It tells a story in which you can see things happen
• It has strong colours that please the eye
• The pictures are large enough to be seen from afar
It looks like things that people are familiar with It arouses interest and questions.
• Barazas are usually too big for flannel graph pictures to be seen from the back.
• When they are used outside, wind may blow the flannel graphs away.
• The apparently miraculous way in which the picture sticks to the board is a distracting novelty.
Remember: Even the best-designed teaching aid cannot replace practical work.
Storage of Instructional Materials
Available teaching instructional materials are often very under-utilized. Often they are stored in dark cupboards, remote stores or in a locked office.
Because of frequent staff changes, everyone forgets or just does not know what is available. Each school should have an inventory of its instructional materials, and every movement, addition or change should be recorded accurately. Any new teacher to the school should be shown the master list of aids and should be encouraged to use them.
Storage of specific aids
• Maps and charts are stored rolled up, but to avoid long searches the titles should be written on the back.
• Slides are best kept in hanging files with a list of contents on the filing cabinet.
• Overhead transparencies and master copies of handouts are put in a master file together with other materials on that special unit or block.
The master copies are given numbers corresponding to the number of the stencils which are stored in or near the stencil room, again filed according to their numbers.
• Models, samples and specimens may be used for a permanent exhibit in the library/media resources centre Good use of teachin g aids involves:
The teacher should ask the following questions:
• Do I need an aid of any kind?
• Will an aid help me to achieve my objective or make the lesson more effective?
If the answer is yes, what kind of aid is best suited to my purpose?
Is the chosen aid available, does it have to be borrowed or constructed? What are the alternatives?
All aids have to be previewed before use. Too often the content of the material chosen is as much a surprise to the teacher as it is to the student! If you look at the aids beforehand, unpleasant surprises are avoided, and explanation or comment can be planned at the right time.
An aid may be used as a means of:
• Introducing a subject, stimulating interest, arousing curiosity.
• Prescribing the main body of the lesson, i.e. as the chief vehicle for transferring information.
For recapitulation, to assist in consolidation of knowledge. Having determined the roe of the teaching aid, the students’ minds must be prepared to obtain the maximum benefit from the aid. Tell them what to look for and explain and comment where necessary.
Make sure the performance is as good as possible. Check mechanical equipment, obtain consent from involved persons/patients/community. Display a little bi t of showmanship.
After presentation, answer the following questions:
– Was the presentation successful?
– Did the aid achieve its purpose?
– Was the objective reached?
Find out the answers to these questions by follow-up activity such as:
• Asking and answering questions
• Questionnaires and assignments
• Weekly tests
Evaluating an Aid
When you are considering the use of an aid or have produced one, it is worth asking whether it meets the following criteria:
• Will the aid help to achieve the objectives?
• Does the aid focus on one main idea?
• Is the aid depicting a real situation?
• Does the aid stimulate imagination?
Having considered all these, you can then go ahead and use the aid. In short, the objective of the lesson should dictate the aid to be used.
It is expected that as you know various types of teaching-learning methods, appropriate use of teaching aids will assist you to deliver your information effectively to the understanding of your learners.