VIDALIA — Carla Greenlee, 15, sacrificed her nose for science and for the chance at a blue ribbon.

Greenlee was working on an experiment for her entry in Vidalia High School’s first science fair.

Her hypothesis was simple — activity would change the quality of a dog’s breath.

She volunteered her own dog and recruited four others from neighbors, and for a week fed them all the same food. Before feeding the dogs, she would smell their breath by sticking her nose in their mouths.

Then, five to 10 minutes after feeding the animals, she would exercise them, and — following the exercise — smell their breath again.

“The exercise didn’t really do anything,” she said. “It was kind of awkward, because you had to open their mouths and hope they would breathe in your face.”

Science teacher Leslie Hurst said she decided to organize the science fair as a way to get her students involved in practical uses of the scientific method.

“They had to be able to do their project and document it where another scientist could come in after them and pick it up,” she said.

For 14-year-old Laura Perilloux, that meant doing a lot of documenting.

Perilloux had a theory that dogs and cats may have a paw preference, similar to how people are right and left handed. To test the theory, she recruited 20 cats and 21 dogs from around town.

She would place a dog or cat treat just far enough into a canister that the animals could not get it out with their mouths, and then observe which paw they used to get the treat out of the canister.

“I did a lot of research on it beforehand,” she said. “I expected most females to be right-pawed and males to be left-pawed, and that’s pretty much how it was.”

And for Kayleigh Jowers, 15, documenting her project’s progress was a tedious one — it was almost like watching the grass grow, except instead of grass, it was basil and sage.

Jowers tested to see if plants grown under a red filter or a blue filter would grow better. For control purposes, she also grew a pot with no filter.

The red filter would block out certain sunrays, while the blue filter would block other kinds, she said.

“I thought the control would do the best, but the red filter did the best, and then the blue, and then the control,” she said.

“I had fun with the experiment, and I still have ladybugs in my bathroom from where I planted.”