How long should my online lecture be? The simple answer is that the video should be long enough to convey your key points but short enough to prevent the viewer from losing interest and quitting the video before it is done. The sweet spot is in the 6 - 10 minute range.
There are two reasons you want to keep your video short. First, you want to hold the attention of the view for the entire video. Second, you want to help the viewer to process the information being presented.
Key Points
A 2021 analysis of the seven academic Bethel YouTube channels shows that the average percentage viewed per video is 44.61%. The majority of these videos were created for CAPS/SEM/GS and are being viewed by adult learners. The reason for the low rates has not been investigated however, two possible reasons are the usefulness of the content and cognitive overload.
Segmentation is the process of breaking up content or video so that the learner is better able to process the information being presented. The rationale behind segmentation is grounded in the Cognitive Theory of Multimedia Learning and its cognitive load principles. It also draws on the pacing principle of the Cognitive and Affective Theory of Multimedia Learning.
Theoretical Rationale for Segmenting
“Segmenting slows the pace of presentation, thereby enabling the learner to carry out essential processing” (Mayer, 2005).
Research about segmentation has focused on pausing the video at key points and then allowing the learner to decide when to move on. The structured pauses allow the learner to process and clear their working memory (Merkt, 2018) as well as invite the learner to engage in some interactivity (e.g. clicking a continue button) while watching the video (Baird, 2017). Thus far, research has not shown a clear reason as to why segmentation works. It appears to be a combination of different factors.
Practical Applications
Keeping students engaged:
- Keep videos in the 6 - 10 minute range.
- Script your lectures so that they are concise.
- Provide information that the student is not getting anywhere else in the class.
- Provided examples of complex or confusing ideas or concepts.
- Integrate video content into course assignments and assessments.
Reducing cognitive overload:
- Use segmentation to break up larger pieces of information.
- Build pauses into longer videos or videos with complex information.
- Make use of YouTube chapters to allow students to jump to key parts of the video.
References
Bétrancourt, M., & Benetos, K. (2018). Why and when does instructional video facilitate learning? A commentary to the special issue “developments and trends in learning with instructional video.” Computers in Human Behavior,
89, 471–475. https://doi.org/10.1016/j.chb.2018.08.035
Biard, N., Cojean, S., & Jamet, E. (2018). Effects of segmentation and pacing on procedural learning by video. Computers in Human Behavior, 89, 411–417. https://doi.org/10.1016/j.chb.2017.12.002
Fiorella, L., & Mayer, R. (2018). What works and doesn’t work with instructional video. Computers in Human Behavior, 89, 465–470. https://doi.org/10.1016/j.chb.2018.07.015
Ingrid A. E. Spanjers, Tamara van Gog, & Jeroen J. G. van Merriënboer. (2010). A Theoretical Analysis of How Segmentation of Dynamic Visualizations Optimizes Students’ Learning. Educational Psychology Review, 22(4), 411–423. https://doi.org/10.1007/s10648-010-9135-6
Merkt, M., Ballmann, A., Felfeli, J., & Schwan, S. (2018). Pauses in educational videos: Testing the transience explanation against the structuring explanation. Computers in Human Behavior, 89, 399–410. https://doi.org/10.1016/j.chb.2018.01.013
Mayer, R. E. (2005). The Cambridge Handbook of multimedia learning. In The Cambridge handbook of multimedia learning (p. 170). New York: University of Cambridge.
Spanjers, I., van Gog, T., Wouters, P., & van Merriënboer, J. (2012). Explaining the segmentation effect in learning from animations: The role of pausing and temporal cueing. Computers and Education, 59(2), 274–280. https://doi.org/10.1016/j.compedu.2011.12.024