Lorraine Walsh was a little dismayed when her overhead projector failed to appear in time for her lecture, but she carried on regardless. Afterwards, her students said how much happier they had been with the session.
"It really got me thinking," said Dr Walsh, a lecturer at Dundee University. "Expecting students to simultaneously listen, read, think and write is really asking too much. Yet we never think about the rationale for using the overhead."
Her unintended experiment led her to research the issue further and Dr Walsh quickly realised that learners found note taking easier in lectures not driven by the OHP.
"Although I was trying to develop a positive learning environment through the use of visual aids to break up the lecture and stimulate discussion, in reality I was compounding surface learning by my use of the OHP," she said.
By abandoning the device in all but a few lectures, Dr Walsh found students were able to take a fuller part in discussions where before they had been passive.
"In some ways they were placed more on an equal footing with me as the tutor," she said. "I had less visible control over the lecture and I allowed space and time for both myself and my students to think and react to what I was saying. There was room for changes of direction and pace within the lecture."
In fact, the use of the OHP had become more of a prop for the lecturer than a productive learning aid, Dr Walsh said.
"While overheads that highlight key themes can be a useful prompt for the lecturer they cannot allow time for students to absorb important points. The display of quotations and graphs on the overhead, rather than clarifying the issue, was merely adding to the confusion. Learners tend to cut out the listening and the thinking, focusing instead on the reading and writing."