In this article I’m going to try to give guidance and ideas for exploiting the OHP and look at:
- What an OHP is
- The advantages of using an OHP
- Some dos and don’ts
What is the OHP?
The OHP is a small machine designed to project an image onto a small screen or whiteboard. If you have a screen, which can be placed above the whiteboard and pulled down accordingly, it will stop the glare. The materials we normally use with it are pens, which can either be permanent, or cleanable. In addition to these there are transparencies (OHT), which you can write or draw on, and a special type of transparency which a text or image can be photocopied onto.
The advantages of using an OHP
Obviously the OHP, being economically and ecologically sound, can dramatically reduce the amount of paper used for photocopies: anything that can be photocopied can also be photocopied onto an OHT.
- Then again, if you want to give your students a record of the lesson, you can give them a photocopied paper version later.
- If you use an OHP you are effectively telling your students that your lesson has been well prepared and not something you thought of just before class.
- Your students can prepare visual stimuli themselves for presentations or class talks, or work together on separate strips of an OHT to put together an article or story, giving them a sense of achievement.
- You can photocopy a student’s work or a model composition onto an OHT and discuss its merits with your class. Similarly you can quickly present the answers to an exercise or a text which has been dictated for students to compare with their own, just as you can project the tape script after a listening exercise to point out anything of note such as new vocabulary to your students.
- The OHP also accommodates different learning styles and multiple intelligences as you can use colour for the text or drawings. Not only are colours and shapes attractive but they will appeal to and help your more visual learners and those who have a higher visual or spatial intelligence.
- There is lots of material that can be used for expressive speaking activities, such as photos, cartoons, maps, charts and diagrams, and of course you can make your own pro-forma game board of your favourite game or even TV quiz show.
- The OHP minimizes the time the teacher spends writing on the board, with his or her back to the class. You have, therefore, simultaneous control over your class and your materials. Materials can be prepared in advance but the teacher can also make additions. If you are bad at drawing it gives you the opportunity to prepare your picture: ‘Here’s one I made earlier’ solves your problem when your students can’t recognise what you are trying to draw. On the other hand pictures drawn spontaneously can of course be kept and used in later lessons. Again, students like this because it is something they have helped to create.
- You also have more control over the presentation of a text or an image since you can choose to modify it by masking or revealing parts of it. The OHP also allows the teacher to make a text or picture instantly available to the whole class. Finally, it offers variety and can be used to change the pace at any point in the lesson, aiding concentration and providing a useful role in discussions, role-plays and many other pair, group or whole class activities.
- Use progressive disclosure technique: mask what the students don’t need to see, in order to focus and control their attention and get them to speculate on what they can see or predict the content of the parts they can’t. Adapt your course book in this way to make it more interesting.
- Alternatively use silhouetted pictures or show them out of focus, or even small pictures of items in one vocabulary field (e.g. clothes) which can be thrown casually on top of each other and ask the students to call out what they can see. Memory activities can also be employed if you show them a picture and then ask them to describe what they saw or what was happening, or show them another which is similar but ask them to describe the changes.
- Use the tip of the pen to isolate or emphasise points, as well as to draw or write on the transparency. You can also cut the transparencies into strips to produce movable pictures. In other words the strips can be put together to form a story, or moved around to change the sequence and your students discuss the order.
- Additionally, the teacher can use overlays or different OHTs to build up a text or an image. Each part of a diagram or chart can also be ‘hinged’ with tape to others, like a book. If you do this the transparencies have to be presented in the same order. However, if they are ‘hinged’ alternately on either side you can change the sequence.
Some dos and don’ts
- Do you know how to work an OHP? Of course you need to find out how to turn it on and off, where the most appropriate mains socket is, and where the best place to put it is. You don’t want yourself or the students to be falling over the leads.
- As well as thinking about where to put the OHP, think about where you’re standing. Can everyone see clearly or are you blocking the students’ view? And don’t forget to make sure you know which way to put the transparency, and how to focus the image.
- OHPs are expensive, and also bulky and breakable so don’t let children play with them. Set them up at the beginning of a lesson and put them away when you’ve finished. Also think about giving instructions before switching on the OHP, as otherwise you may find the students are engrossed in what’s on the screen/board and not listening to you.
- Tell students exactly what’s required of them, i.e. when to copy and whether to take notes or not, or if you will be giving them a handout later. Keep things simple: don’t make things too complicated for the students to understand.
- Don’t look directly at the light, as it will quite literally dazzle you. Finally, don’t forget to switch the machine off when it’s not in use, firstly to save electricity and secondly to make the students focus on what they are supposed to be concentrating on.
The OHP is extremely practical and versatile as every classroom activity can be adapted for the OHP and even the worst technophobe can use it with confidence. Allowing you to have complete control of the class and holding your students’ attention, it is a useful tool for any teacher or indeed worthwhile purchase for any school which doesn’t have one. Finally, as global warming threatens to devastate our world, using the OHP can play more than a small part in saving paper, therefore trees, and the environment.
If you have any suggestions or tips for using OHPs in the class you would like to share on this site, contact us.
Alan Finch, British Council Paris