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Learning Activity
All Lives Seek Balance

Balance A Natural Community

art form sculpture (mobile)
multi-disciplines art, science
grade levels 2 thru 8
you will need lightweight cardboard, scissors, spools of 18 gauge wire, needle-nose pliers, fishing swivels, nail, hammer and board to punch hanging holes in cardboard, paint and brushes or markers.
time 1 or 2 hours
originated by Marcia McEachron


A mobile is a sculptural concept of movement and balance employing simple engineering skills and imagination. All of nature depends on balance to be successful—so does the mobile which imitates the movements of trees, birds, galaxies and growth patterns. The American artist Alexander Calder perfected and elevated the mobile to an art form.
Students will each construct a mobile based in a particular natural community. For example, a freshwater pond, a park with trees.


Discuss: All lives seek balance. Part of  what defines a living being is that it regulates itself to maintain a bal­anced 'healthy' state that harmonizes with its environment. This state of balance is called homeostasis.

When we get unbalanced, we call the result ‘being sick.’ When we run a fever, or get chills, our temperature regulation is unbalanced. 

What are some ways human regulate themselves?

• A constant temperature is maintained by shivering, sweating, panting, metabolism (digestion, burning food).
• Oxygen levels are maintained by breathing faster or slower.
• Heartbeats change to meet our level of activity.
• Bodies also regulate the amount of water, the salinity and pH of our fluids, and certain mineral.s

All living things of every kind balance similar things within their bodies.

What other aspects of our lives do we balance?

(sleep, family, work/play, nutrition, education)

What aspects of our lives do we allow to become unbalanced?

(sleep, family, work/play, nutrition, education)

Whole natural communities and ecosystems (prairie, forest, pond)  regulate themselves to keep things in balance.

What happens when there are too many of one kind of animal and no predators? Think about what happens to the deer herd in suburban areas where there are no deer predators.
A community needs a balance of producers (plants), consumers (plant eating animals and their predators) and decomposers (fungi, bacteria). Over time, there develops a complex system of checks and balances. Each species has certain predators or diseases that keep its population from getting too high, and certain strategies for protecting itself. Other organisms regulate more subtle things, such as the composition of the soil, air and water, etc. When humans introduce a new animal, plant or disease from another continent, or dump chemicals into the air or water, it can be devastating to natural communities-—it knocks the whole community out of balance.  Can you think of some examples?

Choose a Natural Community to Balance:

Students should now choose a community type for the subject of their mobile. Example: freshwater pond, lake. prairie, your local plant/insect community, high desert, tidepool. There are many other choices possible. Every habitat has its own living community. Encourage students to choose local habitat communities such as unfarmed fiields, marshes, even a vacant lot, or a greenhouse.

Inventory: Once the Community is chosen, students inventory typical members of that community. An inventory is a list of visible inhabitants: plants of all sorts, insects, mammals, birds, fish. This will take some research. (A local community will be best. Working locally with direct experience is  more powerful than second-hand experience.) The inventory should include plants of all sorts plus insects, mammals, birds, reptiles and amphibians. Ask students to consider what’s around at night. In summer? Winter?

Does it matter how numerous a species is? Probably. Perhaps a pond mobile might include several frogs and more than one turtle. This should be suggested as food for thought, but the choices belong to the kids.

The inventory is a way of deciding which community members will be represented on the mobile.

The mobile is a visible, tangible way to show relationships within a natural community as they balance each other. For example, young fishes and mosquitoes balance; the fish eat mosquito larvae.

Look at your inventory and decide which kinds of plants can be represented in cut-out form. Which are most numerous and most important to other lives. For example, cattails are crucial to muskrats for food,to redwing blackbirds for nest sites and feeding ground for insects,to frogs for shelter, feeding and breeding,to mink that eat muskrats, to herons and egrets that eat anything they can swallow,to hawks that eat small birds, frogs and snakes, to owls, to dragonflies, to butterflies, and so on


Make the Mobile

1. Begin with a wire about 12" long. Make a small loop in the center. Make a loop at each end.

2. Make a second wire, the same shape as the first. Hang it from one of the end loops on the first wire. Do the same to the other side. Attach a fishing swivel to the center loop. You now have an armature for a mobile that looks something like this:

3. Attach a wire to the fishing swivel to suspend your armature off the edge of a table or desk. Taping a ruler to the top of your desk will allow you to hang your armature further from the edge.

4. Now cut shapes fromtagboard or light cardboard to represent the chosen members of the community. They may be recognizable shapes or free forms with labels. The shapes may be painted or drawn upon. Eyes are helpful.

Caution: to obtain balance a large shape must be balanced on the opposite side by two small shapes that equal the same mass. Experiment with this rule. You will be able to create balance at the angle and pitch that is attractive to you.

5. Attach the shapes to your mobile armature: first use a nail and hammer to punch a hole at the end of your cutout shape. If you connect a fishing swivel between the shape and the loop, your form will turn 360 degrees. If you attach the shape directly to the wire loop it will be a fixed form attached to a moving section.

Experiment: make some of your shapes fixed to the armature and some attached to swivels first. This will make the movement very interesting to watch.

6. Color. Alexander Calder painted his shapes in bright colors and would add one additional color for surprise. Keep colors simple--don't use more than two colors the first time. Simple is effective.

Playing with Dynamic Equilibrium.

Natural balance is not fixed—Balance is active, not static, not fiixed.

Living and non-living systems both survive because they are able to respond to changes in their environment, or changes they have created. As one element grows, another is changed to balance it. If we get hot, we take a coat off, or sweat. Play with your mobiles, using paper clips as weights to change the balance, and see what you have to change somewhere else to make it balance again.

Journal Entries

•   Notice animals regulating themselves to adapt to the weather conditions. Can you see them pant, puff up their feathers or fur, move fast or slow, make trails?

•   List some ordinary things you do that might possibly change the balance in the natural communities around you.

• List a few things you hear on the news that may unbalance the human community.


Making a mobile helps us learn the concept of balance and understand how intricate the processes are that maintain balance. It challenges us to use our imagination to solve simple issues of Balance and Movement. We learn how art imitates nature.


Students will be able to construct a mobile and describe how to balance the parts. Students will be able to give examples of how lives regulate themselves toward balance.

Making Connections

1. Watch the video Calder  which shows him constructing mobiles.
2. Look at photographs of Calder mobiles and see all the different armatures that he invented to create various kinds of movement.


With mobiles representing natural communities, make additional shapes on paper clips representing influences from humans or  natural 'disasters' (a form of pollution, waste, warm water from a power plant, volcano, introduced species with no predator). Hang it on student mobiles and describe the effects.


Videos: Calder's Circus, Calder, Mobiles.
Books: Many books on Alexander Calder
For books and videos try, Minneapolis Institute of Arts, Minneapolis, MN.
Walker Art Center, Minneapolis, MN has a huge Calder stabile and mobile at side of building.

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