You can create the best-looking, most well-written eLearning lesson anyone has ever seen. But for the lesson to be effective, one of the most important things to keep in mind is that more does not mean better. If your lesson plays too long, you run the risk of losing the attention span of your learner and lowering the effectiveness of the lesson in general.
So how long is too long? The answer is directly tied to the average attention span of an adult learner. According to Joan Middendorf and Alan Kalish, Indiana University, "Adult learners can keep tuned in to a lecture for no more than 15 to 20 minutes at a time."
In their excellent article, The 'Change-Up' in Lectures, Middendorf and Kalish found that after three to five minutes of 'settling down' at the start of class, a lapse of attention usually occurred 10 to 18 minutes later. As the lecture proceeded the attention span became shorter and often fell to three or four minutes towards the end of a standard lecture.
I have been teaching classes for nearly 30 years (both online and in-person). Keeping my students engaged (and awake) has always been a top concern. Here's one final quote from the Middendorf and Kalish article (and it's something to which any trainer can relate). One of their colleagues attended a class and observed the following:
"I sat in the back of the classroom, observing and taking careful notes as usual. The class had started at one o'clock. The student sitting in front of me took copious notes until 1:20. Then he just nodded off. The student sat motionless, with eyes shut for about a minute and a half, pen still poised. Then he awoke and continued his rapid note-taking as if he hadn't missed a beat."
In the 1800s, people had very good attention spans. In her article, Keeping Pace with Today's Quick Brains, Kathie F. Nunley cited the Lincoln-Douglas debates which were literally read from paper and lasted for hours. Nunley said that "people stayed, listened, and paid attention."
Back in the Lincoln-Douglas days, there was less competition for the attention span of the debate attendees. But what about today? Why are attention spans getting shorter? More likely than not the culprit is the distractions and experiences of modern daily life.
"Today's mind, young or old, is continuously bombarded with new and novel experiences. Rather than novel opportunities every few days or weeks, we now have novelty presented in micro-seconds," said Nunley.
eLearning and the Common Goldfish
So eLearning lessons can last anywhere between 15 and 20 minutes and still be effective, yes? Ummm, no. The 15-20 minute range was for an in-person classroom with a live trainer. The times are just a bit different when it comes to asynchronous eLearning lessons that will be accessed over the Internet.
According to the article Turning into Digital Goldfish, "The addictive nature of web browsing can leave you with an attention span of a goldfish."
Granted, a learner accessing your eLearning lesson will have a greater attention span than a typical web surfer--or even a goldfish. However, in my experience developing eLearning, I put the attention span of an adult learner at 15-20 seconds per slide or scene. If the slide/scene plays any longer, your learner will begin to fog out.
I know what you're thinking: 15-20 seconds is not enough time to teach anything. If your slide contains some voiceover audio, a text caption or two, and an interactive object controlling navigation (such as a button or click box), 15-20 seconds is perfect. Your student will have enough time to understand and absorb the content before moving on to the next slide.
I encourage students who attend my eLearning classes to try to chunk a one-hour eLearning course into several short eLearning lessons. That would translate into 12 Captivate eLearning lessons (if you use the 5 minute-per-lesson timing) for the 60-minute course.
What do you think? Is 3-5 minutes the right amount of timing for an eLearning module? I'd love to see your opinion as comments below.