Goldfish, tilapia and crabs swim inside the aquariums. Outside, 10- and 11-year-olds press their faces close to study the marine life, then test the water for nitrogen, ammonia and dissolved oxygen.
The aquariums are lined inside a trailer parked outside Mount Airy Elementary School.
Inside, fifth-graders bend over petri dishes, count brine shrimp and work to determine whether the tiny animals grow best in fresh, salt or brackish water.
This mobile aquatic science laboratory, perhaps the first of its kind in the United States, is sponsored by the Chesapeake Bay Trust and Maryland Agricultural Education Foundation Inc.
"This brings the field trip to the school," said Bob Keenan, director of MAEF's Maryland Education Center for Agricultural Science and Technology and the creator of the mobile lab.
"When I'd take kids on a field trip, we'd take two hours to get there and two hours to get back. That was not a wise use of time," he added.
Exhibit trailers are common but Keenan said he hasn't seen anything like the traveling aquatic lab.
Its sponsors spent $25,000 to buy the trailer and $10,000 to equip the lab. Host schools pay about $1,100 for a one-week visit (a teacher travels with the lab). Mount Airy Elementary School PTA is sponsoring the lab for two weeks.
The lab went on the road in January and will have been used by 11,000 students in 21 schools by the end of the school year.
The fish aren't stressed by the public exposure, Keenan said, although some die of other causes. Students learn that crabs eat goldfish.
Fifth-grade teacher Patti Cannaday learned about the mobile science lab from a flier MAEF sent to teachers involved in agricultural education. She enlisted support to bring the lab to Mount Airy Elementary School because it would fit the science curriculum for all grades.
Fifth-graders doing experiments in the lab this week had papers outlining scientific method, but groups working on the projects still had questions.
"We have to count all these [brine shrimp]?" one student asked. No, only the ones that have hatched.
"How will we know if they're alive?" asked another. Check for movement.
Daniele Tellish, 10, took a leadership role in her group's experiment with duckweed, directing her partners to add water containing dissolved detergent to the petri dishes.
"Writing down stuff is boring, but it's fun when you get to do ex- periments," Daniele said about lab work.
Scientists use duckweed to assess the impact of pollution because it is a fast-growing plant, said Tonjia Mayne, who is on leave from her job as an agriculture teacher at Linganore High School, Frederick County, to accompany the lab.
Students had learned about duckweed earlier in Cannaday's class.
"They just call [the fronds] mothers and daughters. They don't have sons," explained Sandy Signorino, 11, of Woodbine.
The mobile lab is concentrating on elementary schools this year, but it also can be used in middle and high schools with more sophisticated experiments, Keenan said.
The experiments use inexpensive equipment, made from recycled materials when possible. The equipment can easily be reproduced by teachers who want to continue experiments in their classrooms, Keenan said.
Three additional trailers are scheduled to join the mobile aquatic lab in the next year. One will focus on Maryland agricultural products and will be sponsored by the Maryland Grain Producers Utilization Board and Maryland Farm Bureau.
The other two trailers, still awaiting financing, would concentrate on agricultural chemicals and food safety and biotechnology in agriculture.
Keenan hopes to make the biotechnology trailer resemble a spaceship's interior, with lessons on growing food for space travel in the 21st century.
"We want to get people to understand that food comes from beyond the grocery store," Keenan said.
He said the trailers are also intended to promote interest in agricultural careers.
"We need agricultural scientists at all levels, not necessarily [doctorates], but we need good technicians," he said.
Pub Date: 4/25/97