On your mark, get set: Science!

Most of today's contestants are studying for four weeks at the Exploratorium's Teacher Institute. The Teacher Institute brings both middle and high school math and science teachers together for classes, projects, and a chance to compare notes. Many of the Institute's participants build smaller versions of the Exploratorium's interactive exhibits to take back to their students. And, of course, they can compete for greater glory on "Iron Science Teacher."

Today's contestants are from California, New York, Louisiana, and Arkansas – a number of them are from Arkansas, in fact. "Some are from rural areas and don't get many opportunities to work with other science teachers," Shore says.

The next contestant, James Arce, is from Arkansas. With the assistance of audience members Maggie and Nadine, he shows how to extract DNA from plant cells (squished strawberries) and animal cells (Maggie's spit) using salt, rubbing alcohol, detergent, and a couple of test tubes. With a Dr. Frankenstein flourish, Mr. Arce finishes by pretending to mix Maggie's DNA with the strawberries. He pulls out a plastic doll with strawberries replacing its hands and face.

"My very own strawberry blonde!" Arce says. Eyeing his creepy creation, he adds, "Maybe I'll put her up for adoption."

Like all "Iron Science Teacher" shows, this one is webcast live. Every episode is archived and accessible on the Exploratorium's website. Well, almost every episode. "We had to edit out one winner," confesses Shore. "It was a very dramatic explosion. Really popular with the audience ... but it was too dangerous. We knew every little kid would want to try it at home." Nothing blows up on this show.

Arce is followed by Melissa Lopez and Tammy Davis, who show how fruit can be boiled to make dyes for T-shirts. They use pipe cleaners and fluffy cotton to explain why the dye molecules are trapped by the fabric. The last contestant is Todd Bauleke of California, who shows how pigments like those found in fruit can combine to produce an artist's palette of colors.

The winner of "Iron Science Teacher" is chosen by the volume of audience applause. Will "Fruit Battery," "Electric Cake," "Strawberry Blonde," "Fruits to Dye For," or "Pigment Mixing" carry the day? It comes down to a clap-off between Paparella and Bauleke. In the end, Paparella's juiced-up stopwatch and calculator win over Bauleke's artistry. All the teachers are beaming.

"Science teachers really deserve applause," says Shore. "This show is one place where they actually get it."

• You can watch the next 'Iron Science Teacher' webcast live on July 21 at noon, PST, at: www.exploratorium.edu/iron_science

It's hard to pick the cleverest ingredients and science activities served up at the "Iron Science Teacher" competition since its debut in 1997, but here are a few examples.

Fruitcake. This special holiday edition featured a reenactment of Galileo's experiment on the Leaning Tower of Pisa (dropping different size fruitcakes, of course) and a model of the digestive system using fruitcake to dramatize constipation. But the victorious science teacher sat on a fruitcake and then drowned it in a bowl of water to show how density affects buoyancy. None of the activities involved actually eating fruitcake.

Golf balls. A carnival game became a physics lesson about conservation of energy as kids from the audience rolled golf balls on a metal track. The activity beat out a golf ball catapult and a biology lesson on fertilization in which a golf ball starred as a sperm.

Plastic bottles.Flying machines and a super-soaker squirt gun lost out to an elegantly simple "lung in a bottle" made from a plastic bottle (the chest cavity), two balloons (the lung and diaphragm), and a straw (the trachea).

Red tape. The only episode not filmed at the Exploratorium was a special webcast from Washington, D.C. The winner used static electricity to levitate a bit of shredded nylon tape, proving that, even in our nation's capitol, red tape has its uses.

Page: 1 | 2