As the group of 15 teachers paddled their canoes into the Middle Branch of the Patapsco River, their leader pointed out a tern ahead — stirring a moment of confusion.
Not a left turn or a right turn, explained Jocelyn Tuttle, who leads Baltimore harbor education programs for the Chesapeake Bay Foundation. A tern — one of many seabirds common to the marshes the group was touring in Masonville Cove.
The educators from schools across Baltimore City had come to see the bay up close, as part of a weeklong summer school intended to improve environmental literacy among teachers, and eventually their students.
Though the bay is close to the heart of Baltimore, the educators said, it's far from the minds of many youth in the city. And many of the teachers are realizing this week how unfamiliar it is for them, too.
In one activity, the teachers were asked to consider how the broader bay watershed affects Masonville Cove, home to the nation's first urban wildlife refuge.
"Did any of you guys know that this exists?" Theresa Dennis asked her colleagues.
Dennis, who teaches science, social studies and reading at Booker T. Washington Middle School for the Arts in Madison Park, said she is always looking for free and local experiences for her students. As she and her colleagues toured the Masonville Cove Environmental Education Center, she started thinking about the ways her students could learn from a trip there.
The bay foundation has been holding this summertime crash course in Chesapeake ecology for about a decade. Organizers describe it as an investigation of "ways that human activities and choices impact the ecosystems and natural habitats of the bay through the collection, analysis, and interpretation of authentic data."
On Wednesday, that included an exercise collecting water samples from the Middle Branch, and seeing up close that its marshes are both strewn with trash and teeming with life.
That followed a trip Monday to Great Kids Farm, the city school system's working farm in Catonsville, and a tour Tuesday of the Patapsco River Wastewater Treatment Plant.
On Thursday, the teachers are scheduled to meet with the water quality advocacy group Blue Water Baltimore and tour Cylburn Arboretum, before venturing back out onto the bay aboard a bay foundation work boat on Friday.
"I'm really hoping these teachers can take away lessons they can bring back to their students," Tuttle said — anything that can help them "connect their actions to life in the water."
Midway through the week, the teachers said that was already the case.
Todd Closson, who leads the PRIDE program for students with behavioral and emotional disabilities at Digital Harbor High School, said he was already imagining his students visiting the farm and the Masonville Cove center. He said African-American students, in particular, don't feel a strong connection to the harbor, but the course experience was giving him ideas of how to change that.
"It helps us to develop curriculum that's hands-on," he said. "I'm trying to find ways to engage these kids, maybe in careers."
Wavie Gibson III, a chemistry teacher at Baltimore Polytechnic, said many students see his subject in isolation. In physics, students can study roller coasters, and biologists can dissect animals. Wednesday's field trip reminded him that students could be exploring what chemistry reactions happen among pollutants in the water.
"It's more than the lab and a textbook," he said.
There was plenty for the teachers to learn, too.
After taking the water samples from the Middle Branch, as well as bringing samples taken from bay tributaries closest to their schools, they learned how to analyze their temperature, electric conductivity and pH levels.
The teachers used equipment that is available at every Baltimore high school, except charter schools, but that few of them had ever used, or had any idea how to help students use.
"Which is most important if I'm a fish?" Tuttle asked the group. The group responded in a chorus: "pH."
As a fish, she explained, the acidity of a waterway "could affect my ability to have babies, or the slime film on my scales."
Staff from the Maryland Environmental Service led the teachers through an activity analyzing a series of maps that is usually presented to middle and high school students. The state agency works with the Maryland Port Administration and the Living Classrooms Foundation on outreach and education at Masonville Cove.
The cove was a popular watering hole more than a century ago. But then it was used for generations as an industrial dump site. It's now home to an active dredge material containment facility, plus the education center and refuge.
The teachers divided into groups that studied maps of the bay watershed or of the prevalence of paved surfaces across Maryland. They came to a conclusion that environmentalists know, but the average student might not: That stormwater runoff flushes pollutants from across the city and the bay watershed into places like Masonville Cove.
They expressed shock at the large number of plastic bottles they saw on their canoe trip.
Rachael Gilde, who helps lead the state environmental service's education programs at the center, reminded the teachers them that the bottles stand out only because they float.
"Think about how much more is in the water column and how much is at the bottom," she said.
They also saw the signs of life in the cove. The port administration began clearing it of trash and debris in 2007. The agency laid out plans for the environmental education center and wildlife preserve on one side of the cove and the dredge site on the other.
Along with the tern, the teachers saw the abundance of birds that have made Masonville a popular spot for birdwatchers. And they saw minnows, osprey and even a crab — albeit a dead one.
After a tour of the Baltimore Museum of Industry on Tuesday, the contrast between the darkest days for the Chesapeake Bay and its rehabilitation since then was clear to Gibson.
"The overall quality of the bay is actually improving," he said. "We're in better shape now but we still have a long way to go."