Faculty can use Tegrity, the lecture capture tool licensed by the University of Alabama, to record their in-class lectures or provide supplementary videos that automatically upload to Blackboard. The in-class lecture recordings, as you might imagine, tend to last about an hour or more. But research shows that for best results, videos should be less than 10 minutes long, ideally lasting only about 6 minutes.
According to research conducted by Dr. Phillip Guo, a visiting research scientist at EdX (a provider of online courses from schools such as Harvard, Berkeley, and MIT) and assistant professor of computer science at the University of Rochester, students in both certificate-earning and non-certificate-earning EdX courses only watched 6 minutes of the videos in the classes, regardless of the length of the videos. Viewing time actually decreases as the videos lengthen, with students watching an average of only 3 minutes on videos that were 12 minutes or longer.
Now, I think there’s an easy distinction to be drawn between the videos in an online course and a lecture-capture recording of a face-to-face course. The former delivers new and unfamiliar content, the latter reinforces content that students first heard in the face-to-face lecture hall. Students will likely not use these two types of recordings in the same way, so any data on length of viewing time won’t take into account those students who consult the Tegrity recording in order to clear up a point that they may not have fully understood during the lecture.
Where this research becomes helpful is when faculty decide to use Tegrity to record a lecture because they will miss class. This use will then be students’ first exposure to this material and would be subject to this 6-minute sweet spot. In order to maximize student engagement with the content, faculty might consider chunking lectures by subject matter or simply dividing the lecture into 6-10 minute portions. Between each video, you may wish to provide a low-stakes quiz for students that will emphasize key points of the brief lectures.