By Dr Clive Dalton
Visual aids to help learning
We know that the brain loves pictures and colour as they help retain information. The brain also loves shortcuts. Chalk and blackboard were deemed primitive when the whiteboard came in, but with all the recent electronic technology, nothing has basically changed towards better learning. The biggest gain was getting rid of chalk dust!
My college days were all chalk and blackboard, and in larger lecture theatres, there were green roller chalk boards, where the lecturer rarely turned to face the class and just kept on ‘writing, rolling and wiping’. Uni students tell me that this still goes on, and the class simply copies what’s written on the board. The only relief was to fly paper darts from the back of the tiered lecture theatre to see how far they would go!
When a student at Bangor University in 1956, emeritus Prof White who had long retired was asked to step in to do some genetics lectures, and he came in one day asking if we could find his 'slides'. They were his 'lantern' slides - on massive bits of glass (about 100mm x 100mm) that were projected by a massive projector which was still there. The slides were in slots inside a polished mahogany box with a leather strap on top to keep the lid on! It weighed a tonne. The projector had a massive bulb that must have warmed the classroom at the same time - and it was still there too. What an antique treasure. I should have purloined the slides for posterity.
We used projected 35mm slides still made of glass that you could put data on, and then coloured transparency film were standard. These visual aids always helped a talk, allowing some relief from endless writing. They also provided a chance without embarrassment to dose off during long dreary presentations when the lights were lowered. A colleague at Leeds University would project his 500 slides – at agonizing pace, of Yorkshire soils (the Yordale series) if it was too wet in winter for a farm trip. His droning delivery put students to sleep in no time, in the nice warm centrally heated lecture room.
The arrival of the whiteboard allowed more use of colour, and to this day you still see speakers using red and green pens, which are hard to see from the back, especially when trying to get the last drop from a dried up pen. Nobody ever seems rude enough to tell them.
The great student trick was to provide a nice new ‘permanent’ marker pen for the tutor before class– and I’ve been caught out a few times. I always carried a bottle of meths!
Then there was the very expensive white board with a printer attached, so at the end of your scribblings you pressed a button and a copy slowly emerged. Then you had to run off copies for all the class. This at least saved the audience from taking notes - and hopefully gave them more time to absorb the contents of the lecture.
Then came the revolution of the Overhead Projector or OHP. I really went to town with this machine using all the coloured ten pens in the pack, even yellow, which couldn’t be seen! We overlaid acetates to build up pictures – what progress! You could get a photo put on an acetate, or photocopy a page from a book and then project it. You could then read it aloud to the long-suffering class. This I’ve been told on good authority, still goes on in University lectures.
I filled my acetates with masses of words and drawings, and in lectures, we read these words to the audience at a slow pace. It never occurred to us that the audience could read 100 times faster that we could speak, and they had reached the end a hundred times by the time we had finished the first line. The result was audience boredom and daydreaming and scant memory later of the message.
Then a standard teaching trick to stop the smarties reading ahead, was to pull a cover sheet slowly down over each line on the acetate while we laboured each point. I always knew that with the bottom lines, the speaker’s cover sheet would fall off, and he’d be forced to let us see all that was left on the slide. I used to start applause for this, and inevitably the audience joined in!
Thankfully our MAF Information Services who prepared visual aids for talks insisted on the rule of only ‘five words per line’, and ‘five lines per slide’. This saved many an audience for sure, but the rule is still regularly ignored or unknown, especially by PowerPoint users.
Death by PowerPoint
Now we have ‘Death by PowerPoint’ so are really no further forward, and in fact things are worse as it’s easier to make PowerPoint slides. You just type out your lecture in PP, and then project and read each slide to the audience. You can then print each slide as a handout – assuming that you have done a great job of helping people learn. All you have done is to make the job of teaching easier, with no proof that you have provided memorable learning.
Then there’s the problem of pointing to the lines you are reading out to the audience. The old fashioned stick in lecture rooms has long gone and smart communicators bring their own laser pointers. These need to be banned, as show your lack of a steady hand, and make the audience spend their time watching where the light is on the walls and ceiling!