Duration and the "Engagement Clock"

"Shorter is better" is a tenet you're likely to encounter, in some form or another, in relation to eLearning, and while it is rooted in established learning theory, it doesn't necessarily mean that you should approach your projects with a prescribed length or maximum duration already in mind; to do so can be unnecessarily limiting and blunt the efficacy of what you're trying to teach. Understanding this tenet, and the connection between time and engagement, will help you better plan your learning and development projects.

Studies do indeed show that learner engagement declines in relation to time. For example, you may hear that videos should ideally be two to three minutes long — that's how long viewers stay maximally engaged — and that videos and eCourses should absolutely not exceed seven to 12 minutes in duration, because by that point, audience engagement will have dropped off completely.

Those thresholds are informed by empirical research, but they don't take into account all the tools and techniques available to maintain learner engagement. 

After all, people frequently enjoy hour+ long movies and "edutainment" and stay engaged throughout. Why?

Because their "engagement clock" — that is, the amount of time they can force themselves to be engaged through willpower alone before their attention wanes — is being continually reset by things like compelling narratives, information and imagery, humor, drama and more: things that keep them actively engaged, eager to hear the next word or view the next scene.

Similarly, eLearning content doesn't need to be short or fastidiously bundled into two- to 12-minute packages as long as it continually resets learners' engagement clocks. For instance, instead of separating your 24 minute's worth of material into three eight-minute eCourses, you could put it all in one eCourse and ensure that every eight minutes within the eCourse (or better yet, every four minutes), there's some sort of activity or moment that causes learners to actively engage and thus, resets their engagement clock. You could also structure the eCourse into three distinct modules and communicate to learners that they can exit the eCourse after each module, return later (when their engagement clock is naturally reset) and pick-up where they left off.

Even just lightening the cognitive load for a short span of time can help learners feel refreshed and feel less like the entire learning experience is one continuous uphill battle.