Secrets of Circles

Circles are pretty amazing shapes.  If you look around, you’ll see that they are everywhere: in the wheels of a car, on the clock on the wall, on the tortillas on your table, and the Frisbees and tops you play with.  This highly interactive 2000 sq. ft. exhibition features 18 exhibits designed to inspire children and adults to ask questions and investigate the answers as they explore the math, science, and engineering of circles. 

Throughout the exhibit, you will see examples of two- and three- dimensional circular forms and learn how circles aid engineers in solving problems. 

You can draw circles on a glow-in-the dark table, go on a circular scavenger hunt, use mirrors to experiment with symmetry, and build a gear contraption to turn a dancing doll. 


While it is easy to spot the signage in three different languages – English, Spanish, and Vietnamese – the cultures that make up our diverse population are included in more subtle ways as well.  For example, Mexican Folklorico dancers demonstrate spinning circles; an Indian Mandala is displayed as an example of how people use circles and symmetry; and a Vietnamese Round Boat demonstrates the functional nature of the shape.


Children of all ages can explore sophisticated mathematical concepts in a hands-on manner.  Designed to encourage children, ages 3-10, and their caregivers to engage fully in math, this exhibition offers multiple ways to appreciate the many uses of circles in nature and by people.

Preschoolers can explore circular objects like coconuts, oranges, and the Vietnamese round boat.  Older children can contemplate the engineering and physical advantage of circles to solve problems, such as pulling heavy loads or providing architectural support. 

Adults may even learn a thing or two about different compass designs or the variety of shapes generated by rotating circles around an axis!


Many of the elements of the exhibit are open-ended, allowing children to create with circles and lead with their own imaginations.  They can carve on a wood lathe or use more modern digital technology to create their own spinning photographs while building their knowledge of how circles and spheres behave.

Exhibit Descriptions

Compass Table:
Visitors draw circle after perfect circle on a glow-in-the-dark table using three different kinds of compasses.

On a Roll:
As balls and discs careen across a slowly moving turntable, children explore the spinning and rolling patterns of two and three-dimensional circles.

Round and Round:
Three sticks, each a different length, radiate out from a center point. Start them spinning and what do you see? Three circles, in three different sizes.

Pendulum Dance:
Back-and-forth plus up-and-down sometimes equals round-and-round!

Spot the Circles:
Visitors look for circular shapes in this circle-full diorama. There are cones, cylinders, spheres, and even a torus or two!

Family of Circles:
Glowing circles slide, whirl and spin, changing into a cylinders, a sphere, and a torus.

Inventing the Wheel:
Visitors compare the difficulty of lugging one brick on a flat platform and one on wheels as they get firsthand experience with the importance of the invention of the wheel.

Visitors use mirrors to experiment with circular symmetry. One slice of pizza becomes a whole pie, one peacock feather becomes a whole fan.

Wood Lathe:
Visitors use a modern version of an ancient lathe, slowly and safely carving the wood into fanciful circular shapes.

Spin Pictures:
Visitors place lights on turntables and set them spinning. A camera catches the motion and displays the striking circular images for all to see.

Bumpy Ride:
What if wheels weren’t round? What if they didn’t have the axle at the center? Visitors play with unusual cars and the rides they take.

Circles in the World:
Visitors pretend and play in a market full of circles from around the globe. Onions, pulleys, baskets, a Vietnamese round boat, and more.

Circle Videos:
With the spin of a dial, visitors explore videos of circles whirling, waving and working in the world.

Gear Up:
People reinvented the wheel by adding teeth to make gears. Visitors build their own gear contraptions to turn a music box dancer, a clock and a drill.

Build an Arch:
Buildings around the world employ the strength of curves and the efficiency of circles. Visitors explore round structures and build a round arch bridge they can walk over.

Book Bench:
Parents and children enjoy cozying up together to read books from many cultures about circles, wheels, and the whole whirling world.

For more information about the goals and impact of the exhibition, please see Dr. Sue Allen's evaluation report (.pdf, 4.4 MB).

This exhibition was made possible by the generous support of



Group Visits

Secrets of Circles Exhibit Guides
K - Grade 3
Grade 2


Awesome Experiments in Force and Motion, by Michael A. DiSpezio

Why doesn't the Earth Fall Up?, by Vicki Cobb


Games & activities
Secrets of Circles Online

Reinventing the Wheel , by Jessica Helfand


Games & activities
Secrets of Circles Online

Big Wheels, by Anne Rockwell

Color Zoo, by Lois Ehlert

Round is a Mooncake: A Book of Shapes, by Roseanne Thong

The Water Hole, by Graeme Base