Balancing Acts


     As John Muir simply stated,

"When we try to pick out anything by itself

we find that it hitches to everything in the universe."

Explore these various representations to discover new ways of understanding.

Balancing Act Simulation

(Flash interactive)

Balancing Act Solution

(QuickTime movie)

Professional Development Presentation

(QuickTime movie)

Penny Ante Science Activity

(PDF download)

In sum, the text from the simulation links the BALANCING ACT activity representations to the course, SCE 5301: Critical Issues in Science Education:

  • This simulation steps through the construction of a physical model to show how a system responds to different internal and external pressures.
  • The upright nail in the wooden base acts as a fulcrum. The 2 larger nails represent the key themes of population and sustainability. The numerous smaller nails represent different topics that impact on critical issues.
  • Population is the overriding variable that most affects the system's ability to sustain itself. In the model, this larger nail serves as the based of the canopy of smaller nails to be balanced.
  • The system is comprised of many distinct factors that are inter-related and inter-dependent. Each of the critical issues is directly impacted by population, and thus, impacts on sustainability.
  • Balancing the entire system is the global goal for sustainability. This model represents a delicately balanced state of the world. Critical issues may have achieved a relative equilibrium without absolute balance.
  • Individual and collective, intentional and accidental, natural and catalyzed actions may change or even remove system variables. The model may maintain a stable form, but it must respond to achieve overall equilibrium.
  • What impact will removing another nail have on this model system? Can you surely predict when/if the system will collapse?
  • If, as in real-world ecosystems, the instability exceeds the balance, the system can no longer be sustained without intervention.
  • As John Muir simply stated, "When we try to pick out anything by itself we find that it hitches to everything in the universe." And so, it behooves us, as we strive to move toward a sustainable society, to study the intricacies of today's critical issues.

Use these extensions from The Subduction Crew website to inspire your own creativity to integrate these activities into your present curriculum.


Suppose your structure is an ecosystem. What portions of that system could you remove without causing a crash? How can you determine, in the natural world, which organisms can be removed and which must be saved? Mountain building, weathering, and other geologic processes impact the surface, soil and substrate that supports life. 


As deposition occurs, structures build; however, what happens if the center of mass of a structure is shifted? How does this apply to the movement of materials around a subduction zone? The rate at which magma cools determines the size of the mineral crystals within the rocks. In contrast to the initial pile of skewed nails, when properly aligned, the lattice that balances is highly stable.


Within the body, there are many systems that must work together to maintain stasis. Adding or taking away chemicals can cause any of these systems to “crash”; thereby impacting all others, and ultimately the whole. Similarly, the Subduction Factory is a critical component of earth systems. 

SCE 5301 - 0T1

Critical Issues in Science Education

Fred L. Fifer, Ph.D. & Rebekah K. Nix, Ph.D.