It may be worth introducing this notion here. In the absence of predators, a population of organisms rises to a level supported by the environment and then levels off barring changes in that environment. When predators are introduced, cycles emerge. The population of prey rises reaching near the support limit. When the predators respond, they essentially nearly wipe out the prey. Then, in the absence of their food (i.e., prey), they starve.

The predator-prey system [local] can be modeled mathematically using differential equations. Duke University provides a very interesting site [local] for learning about such modeling. There are a number of sites that offer Java simulations in which you can manipulate the environmental variables and view the resulting changes in the equilibrium.

Simulation Site

It would be worth revisiting this topic if and when you teach chemical klinetics.