Graduate student Charles Nickerson shows young visitors some of the work that goes on in Julia Kornfield’s polymer physics lab during Take Our Children to Work Day.

Having dozens of beetles crawl on your skin and up your arms might sound like a scene out of a horror flick. But at Caltech it’s called a learning experience. And it’s fun too, according to the kids who paid a visit to Throop Pond on their tour of Caltech.

They were among the roughly 70 children in grades 4 through 12 who attended Caltech’s annual Take Our Children to Work Day. Made possible by dozens of campus volunteers, the event is designed to allow children to see the exciting things that go on at Caltech and to interest them in careers that are important to their future.

During morning tours, each group trekked to two labs or work sites that involved careers in fields from biology to graphic arts. Then the young visitors regrouped for pizza with parents and volunteers at the Beckman Institute courtyard. They went on to make their own ice cream, play soccer at Braun Athletic Center, and watch a high-definition movie, “The Deep” (an episode of The Blue Planet: Seas of Life), in Beckman Auditorium.

The Throop Pond beetles, ladybugs to be exact, were part of an ecology lesson in symbiosis. The lesson helped illustrate the give-and-take relationship that animals and plants of different species develop to survive. The orange bugs with the black polka dots are a popular form of natural pest control at Caltech because of their decidedly unladylike appetites. Adults can eat up to 1,000 aphids in a day, and their larvae, no pushovers, can consume about half that amount, according to Delmy Emerson, associate director for buildings and grounds. That means an abundance of flowers for everyone to enjoy.

To make her point, Emerson produced a swarm of ladybugs taken from a container. They were released at a planter of roses near Millikan Library.

Also on hand at the pond was a campus cat named Mala, who was intent on fishing for mosquito fish. The fish eat mosquito larvae and are stocked to help control the campus mosquito population.

The group’s seven girls and one boy also learned that earthworm tunnels help aerate the soil and distribute nutrients to root systems. Fallen leaves return nutrients to the soil and provide shelter for insects, in a process that sustains intricate food chains.

All in all, you might say the students saw a demonstration of how the Institute’s populations of fish, turtles, and birds, small mammals like squirrels and raccoons, visiting egrets and skunks, and even campus cats help form the urban wilderness we call Pasadena.

Another group of girls and boys toured the polymer synthesis facilities of Julia Kornfield’s lab, where graduate student Charles Nickerson showed off equipment that included “eyeball squishers and shakers” used in research on creating synthetic lenses for the human eye. The lab’s wide-ranging biological and industrial research includes developing new materials to help patients achieve perfect vision after cataract surgery.

Among the 10 sites that opened their doors on Take Our Children to Work Day was a lab where researchers explore the hippocampus, the part of the brain known to be crucial for memory in humans and other animals. Another lab planned a series of experiments designed to teach children the effects of temperature and pressure on everyday objects. Other kids visited the Seismological Lab’s Earthquake Exhibit Center and Media Center, learned about fuel cells, made customized Caltech buttons in Graphic Resources, or assembled handcraft projects at the carpenter shop.

Right after lunch, the students learned firsthand that you don’t necessarily need a lot of fancy equipment to turn a few raw ingredients into creamy vanilla ice cream.

Chemistry graduate student Connie Lu, who works in the Jonas Peters lab, demonstrates how to make ice cream using high-purity liquid nitrogen as a cooling agent.

CAPSI, the Caltech Precollege Science Initiative, showed them how they could make it using nothing more than a couple of plastic bags, milk, evaporated milk, sugar, vanilla extract, plenty of ice, and salt. Then came the fun part-—after the children shook, rolled, and tossed their bag-inside-a-bag for several minutes, it became an “ice cream comet,” to which they added sweet toppings meant to represent dust, rocky pieces, and carbon dioxide.

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