3/8/2007

The Modesto Bee

Mar. 8--STOCKTON -- What gets moldiest: a piece of bread, a Sun Chip or cheese?

The hypotheses are in, the evidence photographed and the data on display. Now students are waiting for the results.

The results, that is, of the San Joaquin County Science Fair, which started this week and is open to the public today at the San Joaquin County Office of Education in Stockton.

A panel of judges perused roughly 370 experiments Tuesday. Twenty purple-ribbon finalists were notified Wednesday and invited to discuss their findings with judges. Of those, several individuals or teams in the sixth through 12th grades will be invited to go to the state competition in Los Angeles.

"When they do the interviews, that's the really fun part," said Diane Carnahan, who works in professional development of math and science teachers and who is in charge of judging this year. "When the group or individual has to come and interact and talk about their project, that's when you find out if they have the depth of knowledge."

The displays, in fact, show telltale signs of being fun, such as use of the descriptive if imprecise word "jillions," to quantify the number of microscopic hairlike bristles observed in an experiment.

"It's been pretty entertaining so far," said judge Wes Van Vuren, a teacher at Colony Oak Elementary School in Ripon, who participated with the idea of exploring whether to get the school involved in future years.

Ripon and Escalon schools didn't participate this year, said Judi Wilson, director of science and special projects for the county Office of Education, but some of Manteca Unified's schools sent projects.

Soap or sanitizer?

The experiments are sorted by type of science, with engineering and physical science in one area, earth science in another, and life science and health science in another spot.

Among the latter projects, two boys took on cleanliness: They tested soap and water against an antimicrobial hand sanitizer.

They pressed dirty thumbs into petri dishes and compared the results to prints after washing for 10 seconds with only water, washing with soap and water, and using hand sanitizer.

They determined that the hand sanitizer worked best, killing an average of 93 percent of germs as opposed to an average of 84.5 percent with soap and water and an average of 55 percent with water alone.

Based on that, they suggested that school cafeterias and bathrooms install dispensers with hand sanitizer.

But their data also left hope for the power of soap; while its average wasn't as good, the experiment found that soap and water killed 100 percent of the germs on one boy's thumb. But it killed only 69 percent on the other boy's thumb, dropping the average.

A significantly more ambitious experiment set out to determine the effects of neem oil on breast cancer cells.

The ninth-grader who conducted that research, San Singh, placed third in the state competition last year in the pharmacology category and is scheduled to speak at the awards ceremony this evening.

Judges Gerald Oliver and Jerome Brown didn't want to make any predictions about winners, but acknowledged that they were impressed by the ninth-grader's cancer research.

Most students wrote about their findings in white and black composition books.

There were the consumer comparisons: Is Arm & Hammer kitty litter the best? (No, Johnny Cat is better). If equipped with only assorted fruits and vegetables for clothing dye, which is best? (raspberry juice).

Then there were tests of rules of thumb: Does eating sugar increase cavities (Yes). Will a plant die if fed detergent? (No, but it becomes unhealthy).

Strict rules on using animals

At least several appeared to deal with earthworms. Administrators had protocols for other animals. Any involving vertebrates, ranging from mice to people, had to be cleared before the experiment began. Project coordinator Connie Oliver expects today's crowd to count animal activists ready to sniff out any maltreatment.

"We have never had an issue, but others have," Oliver said. "So we have very strict rules."

A duo whose proposed experiment included testing their diabetes and altering their blood sugar level was denied. So was a project involving a slingshot.

Of those making the cut and on display, each was assessed by two judges for its accordance with the scientific method, Carnahan said.

As for the mold winner among the moistened bread, cheese and Sun Chip, it was bread.