Traveling circuses entertain millions of people throughout the world each year, with their performing animals, death-defying acrobatics and funny clowns. In Chicago and many other American cities, schoolchildren are also finding out that the circus can be educational.

On the floor of Chicago's United Center sports arena, brightly costumed performers from the Ringling Brothers and Barnum and Bailey Circus hand out meter-long feathers to schoolchildren, while an instructor tells them how to balance those feathers on their hands. "Place the tip of the feather in the middle of the palm of your hand, make sure the feather is straight up and down, watch the top of the feather and begin balancing by moving your hand side-to-side."

A few of the kids manage to balance their feathers for a few seconds, while most watch their feathers fall quickly to the floor. They learn how eyes and hands work together as a team.

There's a lot of laughing, but there is learning here, too. These are some of the thousands of Chicago school kids who are using the circus in their classrooms. Ringling Brothers created the curriculum a few years ago in Connecticut. In Chicago, it has been expanded to dozens of schools, in cooperation with the Science and Math Excellence Network.

Its founder is Reginald Adams, who says "one of the things we think we need to expose our kids to is more math, more science, more reading at an early age, as opposed to waiting until it is too late. The circus is a good vehicle because you are having fun and learning at the same time."

The network is a partnership between the hospital where Mr. Adams works, and the Chicago Public School system. It looks for ways to improve math and science instruction to the thousands of mostly low-income children who live on the West Side of Chicago.

Network board member Jim Duffy says the circus can be used in many math and science lessons. "When you think about the high-wire act or the trapezes, some of the science concepts that might be behind that," he says. "Or, on the horses, the gentleman who rides between two horses at once, you can talk about the centrifugal force."

Kids as young as five years old are figuring out how much an elephant weighs, while older children study the economics and geography involved in running a circus. Patricia Smith is a math specialist with the Chicago Public Schools. "How much food do they need to buy, to carry with them to feed not only the animals, but the people? What distances to they travel and what distances do the performers come from? The performers come from 40 different countries," she says.

As the circus show begins with a parade of animals and performers, teacher Randy Shuma points out that there are a lot of people working for the circus whom the audience does not see. There are medical staff for performers and trainers, teachers for children in the circus. Mr. Shuma had his students research circus careers. "I think they understood that there is a multitude of things you can do out there. There are opportunities in areas you would not even dream of. For someone who likes to travel and likes the idea of that kind of excitement, it is the perfect opportunity," he says.

Thirteen-year-old student Yesenia Rodriquez wrote a report on acrobats. She says she was amazed at the years of practice the performers have to put in before they can think of working for a circus. "It was kind of fun; I got to learn about exotic jobs. You know, most people work in business, in an office," she says. "I got to see how people have fun doing their jobs. It is more like a sport."

Ms. Rodriquez says she likes to watch the circus acrobats, but says flying through the air is a little more excitement that she would want in a job. She plans to be a police officer someday, which is exciting enough.