Sharyn Denbow and Jean Kirkwood of C. Milton Wright High School carefully noted the cormorants and egrets flying overhead.
Tom Trafton of Havre de Grace High filled a white plastic bucket with bay water and grasses.
Several others in the group plotted their location in the Susquehanna Flats on a map.
They were part of an educational trip aboard the recently restored Chesapeake Bay skipjack Martha Lewis.
They also are Harford teachers.
"It's like a vacation," Mr. Trafton, an environmental science teacher, said of the overnight voyage Wednesday from Havre de Grace to Worton in Kent County.
It was also an opportunity for the 20 teachers to learn about environmental issues. "It reinforces things you know already and lets you learn other things," Mr. Trafton said.
The sailing trip was part of a weeklong workshop taught by Dennis Kirkwood, assistant supervisor of science and environmental education for the county schools, and Joppatowne High teacher Steve Hillyer. The three-credit course included a range of activities for the teachers, including canoeing on Otter Creek and a tour of Harford County's wastewater treatment plants.
"It's the best class I've taken since my undergraduate days," said Charles Braungard, a music teacher at Aberdeen High School. "It's an awareness class."
The course was intended for all kinds of educators. Janet Ruckle, a media specialist at Roye-Williams Elementary in Havre de Grace, took it because "librarians like to know a little bit of everything."
Sue Denicola, a kindergarten instructional assistant who will teach at Joppatowne Elementary this year, said the workshop gave her an awareness of how everything in the environment affects everything else. "You don't realize how wonderful Harford County is," she said.
That's exactly what the managers of the Martha Lewis hoped to accomplish when they launched the 39-year-old skipjack in March. "The Martha Lewis is set up for use as a work boat, and for education and as an ambassador of goodwill for the upper bay," said Liz Rawl, who manages the boat with her husband, Allen, for the Chesapeake Heritage Conservancy.
Dr. Randy George, who financed the $130,000 restoration of the Martha Lewis, was also on board the Martha Lewis Wednesday. The Alabama neurosurgeon, who owns a historic home in Somerset County, was watching a dream come true as the teachers learned about the skipjack and its oystering history.
"The boat is a touchstone," Dr. George said. "It opens up all kinds of ideas for people."
In addition to educational bookings, the Martha Lewis, which docks at Millard E. Tydings Memorial Park in Havre de Grace, is available for charters.
"We keep the Martha Lewis alive by offering public charters for passengers," Mrs. Rawl said. "We don't want to lose the culture that goes with oystering."
A "Cruise to the Horizon and Back" is offered Thursdays and Saturdays from 5:30 p.m. to 8 p.m. The cost is $10 per person, and reservations are recommended. Call (410) 592-2170.