"What's the one thing you do not want to do with a 25-pound brick?" scientist Nick Williams asks a group of kids.
"Drop it," they all yell.
He then lets it dramatically slam onto the concrete floor, prompting both the kids and parents to burst into giggles.
Williams waits until he has regained the crowds attention and puts the brick onto a table. He asks 10-year-old Caroline Greenley to blow into a straw attached to a bag under the brick.
When the 25-pound weight lifts off the table, the kids' eyes widen and they cheer.
Williams keeps his audience entertained with an array of jokes and fun experiments, but the lessons he teaches about air pressure, liquid nitrogen and electrical currents are serious.
As he did two "Fun With Science" shows at the World of Wonders Museum on Wednesday, Williams' main focus was to spark an interest in science through entertaining experiments.
"We like to have kids get interested in science at an early age. Most schools do not have the time, energy or money to have much of a science program," he said.
Williams is retired from the Lawrence Livermore National Laboratory and spends his time educating students through a variety of programs the lab offers. At least one fifth-grade class comes every day to the Livermore laboratory to learn about science.
The World of Wonders Science Museum asked the lab to put on a show Wednesday to provide something for Lodi kids to do during winter break, said Sally Snyde, president of the museum.
"It keeps the kids entertained and interested in science while they are out of school," Snyde said.
Lodi resident Carrie Martin manages the "Fun With Science" tours for the laboratory. Martin, who is a prospective museum board member, collaborated with Snyde to bring the program to Lodi.
"With World of Wonders being remote in the Valley, we need to reach out even farther and integrate our programs," Martin said.
Williams continuously asks the crowd questions — and asks kids to help him with demonstrations that at times can seem dangerous.
Nine-year-old Lucas Smith looked a bit frightened when Williams told him he would be helping him with an liquid nitrogen experiment — mainly because Williams had just finished describing how a bare hand would shatter to pieces if it was submerged in liquid nitrogen and then hit.
Smith's face quickly changed when Williams dipped a glove in the liquid nitrogen container and let Smith crunch it up into little pieces.
There were also some worried faces when Williams asked four volunteers if they were ready for electricity to pass through their bodies.
Madison Lozano, 7, Alyssa Clayworth, 8, Caden Gilbert, 7, and Demetri Berear, 6, held hands and passed an electrical current through their body from a copper pipe to a fluorescent light.
The crowd roared with laughter when Gilbert's shoes, which had lights in the heels, unexpectedly started to flash.
While the kids are having a blast, Williams hopes they are also learning how to think about science.
"I want them to be excited about science and give them an incentive to put together a science fair project or excel in their science classes in middle and high school," he said.
After watching her daughter participate in the electrical current experiment, Stacey Lozano said she appreciated that the program kept all of the kids' attention and was educational.
"When you are reading and learning about stuff, it is cool, but every time you get to do things hands-on, it makes it more real," Lozano said.
For more information on similar programs, go to www.wowsciencemuseum.org and sign up for the museum's newsletter.