WHAT CAN WE DO about halitosis?
Alexis Mason knows. She knows common bad breath is caused by bacteria, which can be killed by mouthwash.
The seventh-grader at Chinquapin Middle School used her own saliva, a microscope and a bottle of Listerine to demonstrate. Hers was one of the intriguing exhibits this weekend in the 16th annual Morgan State University science fair.
Morgan had a record 210 entries, and the topics were limited only by the students' extraordinarily fertile imaginations.
Some of the topics were beyond lay comprehension ("Two Forms of Glutathione Conjugate Transport Protein Residing in Different Subcellular Compartments," by Ethel Morgan, Baltimore Polytechnic Institute). Others invited further examination ("Solar Still," by Autumn Myers, Northern High School).
Lauren Duerling, of Sacred Heart of Glyndon, examined the effect of various substances on the growth of plants. The graphs in her exhibit showed she'd tried several: water, coffee, tea, after-shave. The winner? Tea grounds. (After-shave killed the plants.)
"My hypothesis is that it's the acid in the tea that helps the plants grow," said Lauren, 11, who wants to be a pediatrician.
Aaron Cormack, an eighth-grader at Parkville Middle School, was in the second year of an experiment in progress. Last year, he determined the blade shape most effective for producing electricity in a wind turbine. This year he's experimenting with the gears in his turbine, driven by a common house fan. Aaron, 14, already has his sights set on the Naval Academy.
Courtney Schlaffer, also of Parkville Middle, blindfolded friends and family members and asked them to drink and identify various types of milk: skim, whole, low-fat and so on.
Generally, blindfolded participants couldn't identify the type of milk they were drinking, Courtney discovered. Her mom, she said, did the best job. Her experiment, she wrote, was designed to get people to "switch to healthier milk."
Science fairs haven't changed much over the years. But the Morgan fair showed plenty of signs of the thinking that underlies the Maryland School Performance Assessment Program. Students develop a hypothesis an informed guess then test it in an experiment, describing the results with charts and graphs. Then they report on whether the hypothesis held up.
Brice Dobry's didn't. The Perry Hall Middle seventh-grader thought the best lubricant for the axles of his model car would be graphite. "This experiment proved my hypothesis wrong," Brice reported. The best lubricant? Wesson oil.
There were very young scientists at Morgan, too. Christina Irby, a 7-year-old second-grader at Montebello Elementary School in Baltimore, demonstrated that there is enough electricity in the juices of the lemon, orange, kiwi, pineapple and apple to run a digital clock.
"The purpose here is to help students take charge of their own learning," said Christina's teacher, Gloria Hayes.
Education Beat's favorite exhibit was mounted by Craig Lindemann, an eighth-grader at Perry Hall Middle. His experiment, "What Is the Relationship Between Age and Steadiness?", asked participants to insert a "probe" into nine holes of progressively smaller diameter. Touching the sides of the holes activated an electrical charge and demonstrated unsteadiness, a phenomenon with which Education Beat is familiar.
Craig's hypothesis was that steadiness would increase in the teens years, level off between 20 and 40, and then dip. His hypothesis held up, although the steadiness slide in the older years wasn't as dramatic as he had expected.
His experiment, Craig said, should have application in nursing homes and senior centers as they plan activities.
Morgan professors Russell Kelley and Anasuya Swamy, who organized the fair, pronounced it a success. The Morgan event, LTC Kelley said, is unusual among science fairs because about 60 percent of the exhibitors are minorities, most of them from Baltimore City.
"Exposure is the key," he said. "Last year's international science fair in Hamilton, Ontario, had about 1,100 participants. Twelve of them were minorities, two of them from Morgan.
"We're trying to convince kids through science fairs that science isn't dull. It's fun and exciting, and anyone can do it."
Pub Date: 3/24/96