Fun with science

Published 5:10 am Thursday, May 20, 2010

Sixth-graders Sally Peterson and Olivia Stevens have a lot in common: They both live in Mower County, they’re both on the 4-H advisory committee and they both have a niche for microbiology.

Sally and Olivia both placed in the top three of their category at the South Central/Southwest Minnesota Regional Science and Engineering Fair on May 1 at Minnesota State University, Mankato.

“This was such a coincidence,” said Rae Ann Peterson, Sally’s mother. “We know each other through 4-H and they both place in the same category.”

Sally, 12, finished in first place in the microbiology category for her project “The Soil’s Alive.” She compared plant growth in two soil samples — one with microorganisms and one without. To kill the microorganisms in her one sample, she baked the soil in the oven overnight.

No plant life grew in the baked soil. The other soil sample with microorganisms grew normally. Sally received first place for her project, which took about two months.

Though Sally’s project earned her first place, she didn’t quite get the results she expected.

“I thought the one that was baked would have grown even the slightest bit but wouldn’t have been as healthy, but it didn’t grow at all,” she said.

“It taught me how important microorganisms are to the world,” she added.

Olivia, 12, took third place in microbiology for her project, “How Much Bacteria is Really on a Pacifier?.” She tested the bacteria levels on used pacifiers and one unused pacifier.

Olivia came up with the idea for the project because she often babysits. She dipped cotton swabs in boiled water, then rubbed them on pacifiers. She then allowed the bacteria to grow in petri dishes to see how much bacteria grew and what kind of bacteria grew. The project took Olivia about a week to complete.

The unused pacifier that came straight from the package was the cleanest; however, Olivia said she was surprised how much bacteria was still on it.

“I thought the control pacifier that came out of the package had more bacteria on it than I thought it should have,” Olivia said.

Last year, Olivia tested water samples to see how dirty each was.

“Last year I had done another microbiology project,” Olivia said. “I babysit, and a lot of kids use pacifiers, I sort of continued the project on microbiology on how dirty pacifiers are.”

Olivia’s mother Cindy Stevens had three children compete at the event, and she previously served as a judge for three years. She said it’s an excellent experience for the children.

“I think it’s exciting to see how innovative these children are,” Stevens said.

Sally attends Blooming Prairie Elementary School. She lives in Mower County with her parents Rae Ann and Daryl.

Olivia is home schooled, and she lives in Austin with her parents Brian and Cindy.

Both girls had younger brothers who competed in the science fair. Nathan Stevens, 11, placed third for a project that tested the kinetic energy of magnets using Gauss magnetic rifle. Clint Peterson, 9, received a ribbon in the physical science category for a project testing how different liquids cause nails to rust.

Both Stevens and Peterson said such experiences help their daughters learn to be comfortable talking with adults.

The regional science fair was quite a bit of sitting next to their project as about six judges each walked around and asked the participants about their projects. The girls had to explain their projects to the judges and answer questions. Judging took about three hours.

The judges passed on some useful information to the girls. One of the judges told Olivia how to position her petri dishes to not have any other mold growing besides what she collected for the samples.

A judge told Sally to test soil samples from different places. Another judge suggested she bake her soil samples for different lengths of time to see how the growth rate varies.

Both girls are eligible to be invited to the state science fair.


Both girls are active in Mower County 4-H, and they both plan to use the projects for 4-H at the Mower County Fair. Both girls are also on the county advisory board, a group of adults and 4-H’ers that provides leadership and makes decisions about 4-H.

“They’re just kind of starting in the young leadership and taking hold of it,” said Melissa Koch, Mower County 4-H program coordinator. “I see a huge potential in both of them to step up to be great youth leaders in the county.”

Koch described Sally as a shy leader who has good ideas and isn’t afraid to bring them to a group. Koch said Sally is working on an idea to restructure the county’s Share the Fun project. She’s also actively involved in her local Udolpho 4-H club.

Koch described Olivia as an excellent leader who has the ability to get a group of people together around an idea. Koch said Olivia does a good job of getting her younger siblings involved in events. In February, Olivia attended an overnight event called BLU, Building Leadership and Understanding. Since then, Koch said she can see that guiding Olivia’s leadership.

“They both have that initiative to step up and try,” she said.

Along with their budding leadership skills, Koch said she hopes the girls can serve as an example to other 4-H’ers to show that school projects are easily adaptable to 4-H.

“That’s what 4-H is about: continuing and improving on something that you’ve already established,” she said.