Presenting the large
stationary image
Presenting the large stationary image
Start calmly
Allow students to absorb the projected image before giving explanations:
wait 15 to 20 seconds (the time needed to activate the subject-related parts of the brain; the long-term memory resides all over the brain)
Point with a pencil to key points on the transparency, not to the screen.
Thus you remain facing your audience and can monitor its reactions.
Provide information step by step
Show only that part of the transparency which is relevant at that point
 
in time. This arouses student curiosity and leaves you clearly in command.
Then cover the part already discussed and proceed by uncovering what
 
follows. This creates a calm learning environment. Then present the overview with the final impact by revealing the ENTIRE transparency.
 
By the way, covering a part or parts of the transparency stimulates both teacher and student, but do not overdo it. Trying to show only a very small part of a transparency can be counter-productive. It is more effective to show the entire transparency and use a pointer to highlight the area where students should focus. A black bar on the screen can also be used to direct students' attention to the point where they should begin interpretation to get a logical build up of understanding.
Questioning is the key
An appropriate picture always enriches an explanation, even when you
  are not directly referring to it.
 
The transparency acts as an eye catcher, creates a positive atmosphere and aids retention.
Don't be tempted to give away the story too soon.
  Questioning is ALWAYS the best method because the overhead projector is first and foremost a medium for discovery learning.
   
Ask a question, provide a few seconds "wait time" and invite a student
to respond.
Let a student come forward to point out and explain an aspect of the
  projected image.
Let students unravel clues in the image.
Let students individually or in small groups design their own questions
 
and answers. Let them take notes. Apply their questions when designing
later tests.
The question method stimulates and activates the mind. Moreover, it prevents you from talking too much and from students listening too much.
 
The question method requires that the teacher is aware that asking questions about a projected transparency is a lot more productive than telling stories to it. Use the 20 second wait-time which students need to gain a first impression of the image, to formulate an effective question rather than to prepare your story


Questioning is the key

Excessive exposure is
damaging -
keep the surprise effect.
Show 3 to a maximum of 10 transparencies perlesson and
ensure that you reveal
them at the critical moment

"Let Lenny advise you"
The overhead projector and screen
in the classroom
The wall as a large projection screen
Place the projection screen in the darker corner in front of the classroom, or ensure that incoming light does not reflect on to the screen. In a proper set up only one curtain needs to be closed on a sunny day
The bigger the screen the better (1.20 metre x 1.20 metre is advised). A white painted square on the wall also serves very well as a projection screen. Try to have overhead projectors and screens installed in most classrooms to facilitate regular use. If projected onto a relatively small (electronic) whiteboard the large image effect might be lost - installing an additional big screen is worthwhile.
 
Place the overhead projector directly on your desk - or better still, sunk into your desk off-centre so that you can annotate your presentation without blocking the projection. Alternatively, the OHP may be mounted on a trolley: it can be pushed into a corner when not in use and remains accessible.
 
The image is projected over your shoulder.You keep facing your class; it is easy to write or draw (with washable ink) on the transparency or to cover some parts not being dealt with at that particular moment.
You remain in eye contact with the students and monitor the level of engagement. This work situation is especially effective for inexperienced teachers as it helps maintain class management simultaneously with lesson presentation.
 
Ensure that the transparencies are within easy reach for direct use. Also, keep your self-designed transparencies arranged in the correct sequence.
Use an overhead projector with a strong lamp: 250 watt OHPs were common in the last century but 400watts is highly recommended now . The higher wattage provides greater contrast, deeper colours and more legible text. Presentations are much more vivid and remain visible even in sunlight.

Types of software for the OHP
Basically there are three packs available.
 
Theme-bound series, often of German origin, containing 5 to 40
transparencies, designed to teach one complete subject with the help of student worksheets.
Transparency series linked to a textbook that students use with a
selected number of images from that book. Publishers provide these these packs to help teachers to work more effectively with the book.
 
OHP-encyclopedias with the most important topics arranged for
each school subject offered in secondary programs such as Geography and Physics. These encyclopedias are visual data banks designed for students from class one to end grade. The encyclopedias are also suitable for higher education programs as they contain a wide range of rich, visual data to illustrate specific concepts or provide an overview.
 
 
Varying opinions of what types of packs are usefull. Some overhead projector-users want to use only those transparencies which show the same images presented in their student's textbooks or CDs. In this way, students can view the images again at home. Other users view transparencies as extra teaching tools to provide visual clues. They often consider transparencies cost effective and more flexible than wall charts and maps or use them as part of their multi-stimuli lesson strategy.


TTE's Visual Geography Encyclopedia with 587 transparencies
Transparencies force
the thinking cogs
into motion

Processing visual information
Young people'sbrains react
more strongly to visual stimuli

Some Teaching suggestions
The global overview, for which many transparencies are designed, provides a structure which serves as a memory anchor enabling students to work independently and with confidence. Transparencies offer a powerful aid for teachers for this.
Use transparencies to put students to work individually or in small groups. Student activity often is based on independent learning and transparencies help teachers to instruct effectively. You only have to spend a few minutes to provide the information and crucial knowledge. New information can be processed meaningfully - the visual can be recalled easily later, when working alone.
Use transparencies to introduce new concepts. Visualization helps pupils to distinguish essentials from supporting information, an important skill when making notes.
Showing transparencies during the presentation of your lesson helps students maintain the lead of the story and to focus on key concepts.
Use transparencies to repeat and test key concepts and processes
Show similarities and differences between similar processes, organisms or structures by using different combinations of transparencies.
Address the needs of pupils with language or abstract-application problems by providing your lessons with concrete, visual material.
Encourage students to come forward to point out and explain aspects of the projected image.
Let students individually or in small groups generate their own answers. Let them take notes and use the answers in later tests.
Stimulate students to use these transparencies in their own presentations.
Let students unravel clues in the image. Design quizzes with the transparencies as a premise.
Transparencies provide strong visual reinforcement. Dictate questions based on the images to be used. Use a quizz to test the desired knowledge and skills.
You can write on the sheets with washable ink and use them time after time. Select an image and extend it with your own notes - write and add as much as you desire.
Develop repetition strategies with which you can combine the transparencies and other teaching material.