While the lecture has come under attack as of late for being too teacher centered, we, as teachers, still use it as a method. I honestly believe that most teachers recognize that lecturing non-stop is not good teaching and attempt to create more student centered lessons as well. The reality is though, teachers have information that students need, and presenting that information orally is an efficient way of disseminating that information.
I have trouble believing that there are many teachers who stand in front of the room and just talk at their students day after day after day, but I think all teachers do it from time to time. That being said, we have to ask the question not only “When is it acceptable?” but we must also ask “How can I lecture and present material in the most meaningful way?”
Obviously, one of the most common means of presenting information is via a PowerPoint presentation. What an awesome tool PowerPoint can be, but, boy, can they be used poorly. Since I teach Public Speaking, I have done some research on presentation tools and given a great deal of thought to how to use them well. As a teacher, I tend not to use PowerPoint a whole heck of a lot–not for any particular reason, per se; I just don’t use it a whole heck of a lot.
That being said, as we think about using PowerPoint, I have a few rules of thumb that I follow. A PowerPoint should enhance a presentation–it should not be the presentation. There is nothing I hate more than listening to a speaker read PowerPoint slides to me. I also hate when students just mindlessly copy slides into their notebooks. If the intention is that students have the material on the slides in their notes, why not simply print out the slides? If you could simply hand out the presentation to kids and not actually speak, why not do that and save time? There is something to the idea of presenting material in different formats for students, but the same exact material orally and visually at the same exact time? That just doesn’t feel right to me.
Which brings me back to the whole idea of just reading the slides. PowerPoints are visuals. So let’s use it that way. A PowerPoint full of pictures or images is far more meaningful and powerful. Research is pretty clear–providing pictures helps many students learn. PowerPoint is a great way to do that.
So just how many words should be on a slide? A valid question indeed. I constantly remind my Public Speaking students to not overfill slides. My mantra is clear: “Slides are free” and “more slides” Sometimes I feel like Oprah (and you get a slide, and you get a slide!) But in all honesty it is true. There is no reason to limit the number of slides. Let’s say you put 36 words on a slide; that’s a number that I’ve seen bandied about on many blog posts. Simply reading those 36 words is boring to students and a waste of their time, but it also overloads their brains. The latest research suggests that reading aloud to students from the PowerPoint actually decreases comprehension because the brain is trying to do two things at once–listen and read. So if you put up 36 words and wait for them to read it, you have to actually wait quite a long time. The average reading speed is 180 words per minute, which means it would take about 12 seconds for the average person to read 36 words. Are you really willing to wait that long? 12 seconds is a long time to wait and stare at a class during a presentation, especially if you have multiple slides like this. Breaking up the slides (and including mostly pictures–not words–helps to alleviate this problem.
All in all, what I am suggesting here is that we use PowerPoints thoughtfully and judiciously. Not every presentation needs a PowerPoint, nor does a PowerPoint necessarily enhance the presentation. As teachers, we may need to lecture from time to time. That doesn’t mean we need to use bad PowerPoints.