CONCORD -- Eco-Bots rocked, rolled and vibrated up a storm at the Delta-Diablo 4-H clubs' National Youth Science Day.
In the facility of the Loyal Order of Moose Lodge 567 -- and all across the country as seven million 4-H'ers participated in the 2012 National Science Experiment -- matchbox-car-sized robots tackled oil spills and other environmental disasters.
Community leaders hoped the event would spark interest in science, technology, math and engineering. Kids hoped it would be fun.
And it all started with a toothbrush.
"First, we had to break a toothbrush," explained Nicholas Arroyo. "Then we got double-sided tape, put it on a little battery that vibrates, put the red wire under the battery, the blue wire on top of the battery, then put more tape on so it pressed the wires onto the brush head. Then, it worked!"
The 9-year-old fourth-grader was accompanied by his grandmother, Connie Jauregui, who served as a coordinator.
After mobilizing the Eco-Bots, the kids were instructed to build "retaining walls" to surround the printed-on-paper oil spills their bots would attempt to sweep.
"They used straws, but found they needed something more substantial and pretty soon, they were using cardboard," said Jauregui.
Alexandria Hanlon, 13, an eighth-grader, was a junior leader.
"My Eco-Bot did really well, aside from running over the straw barricades," she said. "I learned that vibrations from the batteries would move the Bot. I thought it would just bounce up and down, but it traveled!"
Alexandria joined 4-H five years ago when a friend showed her how the club could teach her about training dogs and riding horses. To the owner of three horses and one tricolor Australian shepherd dog, named Zander, it was a golden invitation.
"I learned everything from sit, down, heel -- to agility, where your dog jumps over fences and runs through plastic tubes," she said.
It sounds a lot like an Eco-Bot, vibrating its way across an oil spill, and both activities feed her dreams of a future career, riding horses as a rodeo queen and training dogs.
"Last night helped me a lot with science because now, I really want to see what will happen if I mix chemicals or make something," she said.
In addition to Eco-Bot creation, science displays were presented by children attending the competition.
One display asked, "Do pigs sweat?" Another, "Who ate my roast beef sandwich?"
But mostly, the kids invented, which is half of 4-H's learning-centered mission.
"I had one Bot that went crazy. I grabbed it up and just had fun with it," Nicholas said. "Now that I learned to put it together, I think I can make other ones."
Jauregui said the third stage of the experiment, where rice or bird seed is scattered on the "oil spill" and Eco-Bots go to work sweeping it aside, was abandoned -- in the name of science.
Instead, young minds were turned to new possibilities: chaining four Bots together and discovering circular patterns; attaching balloons and observing differentiated capacities for acceleration; constructing tunnels and testing Bot dexterity while maneuvering through an obstacle course.
Animal programs and the local chapter's weeklong Camp Angwin draw the greatest interest, according to Jauregui, but Nicholas said his plan to become a marine biologist might involve building more robots. Which is what he will be doing next -- right after he and his grandmother finish showing his prizewinning chickens and rabbits at state and county fairs.
To find a 4-H youth development program, visit http://www.4-h.org/.