Contributed to the TLCo-op by Emily Gaston, Graduate Research Assistant of the Center for Instructional Innovation and Assessment, 2021.
The Theory of Margin, also known as the Power-Load-Margin (PLM) formula was McClusky’s major contribution to adult and higher education conceptual theories. This formula sees learner motivation as a measure of the learner’s access to resources (power) that will offset the demands of their lives (load). Below we will take a look at what this theory is, how it can be useful, what it means for your classroom.
Power
Power refers to the resources a learner has access to within their lives that will help them offset the demands or commitments they have outside of the classroom. Examples of power may contain economic wealth, a general sense of well-being and health, supportive community connections, and positive coping skills.
Load
Load refers to the demands placed upon the learner by themselves or by society as a whole. Examples may include child rearing, working in addition to attending school, intrinsic goals set, or other things that can increase a learner’s stress levels and occupy their time.
Margin
Margin illustrates the dynamic relationship between power and load. The PLM formula could be set up like so:
Margin = (power)/(load)
In order to illustrate how this formula translates to adult learning motivations, we can look to Adult Education Quarterly for the following examples:
| Power Value | Load Value | Margin Value | Formula | Formula Implications |
| 2 | 4 | 0.5 | 2/4=0.5 | (Deficit of Power to Handle Load)/(Crisis of Excess Load Pressures) |
| 7 | 7 | 1.0 | 7/7=1.0 | (Breaking Even)/(Barely Holding On) |
| 4 | 2 | 2.0 | 4/2=2.0 | (Surplus of Power to Handle Load)/(Space to Maneuver) |
Adult learners have the ability to carry a high load level, but will only have higher levels of perseverance and success in higher education if their power can match or exceed their load. Instructors can inadvertently add to the learner’s load through their teaching practices. Rigid, authoritarian styles of educating may create a surplus load for students who require flexibility and should have their experiences and opinions be respected.
Strategies that Take into Consideration the Power-Load-Margin Formula
- Course planning that takes into consideration various demands for a more balanced load.
- Course assignments and assessments that vary in intensity appropriate for the discourse and course level.
- Check-ins with students to learn more about the demands and resources available to them.
- Feedback cycle to help adjust demands as needed.
Resource: Power Load Margin: A Theory for Adult Learners, Howard Y. McClusky
Image Attribution: “batteries-1379208_1280.png” by Michał Jamro is in the Public Domain, CC0