Stella Schoberg smiled, braces gleaming, as her class project sank to the bottom of the Chesapeake Bay.
She and her fourth-grade classmates at Friendship Valley Elementary School in Westminster spent much of the school year learning about the estuary — how "dead zones" form, why warmer water holds less oxygen and how oysters reproduce and grow, filtering pollution and sediment from the water.
They capped it off building two dozen gumdrop-shaped blocks of concrete on which oysters can grow. Carroll County students were among hundreds in Maryland who helped with an effort to bolster the bivalves and the countless other creatures who rely on active reefs to thrive.
On Wednesday, 10-year-old Schoberg got to kick off her summer watching the so-called "reef balls" serve their purpose.
A broad partnership led by the Maryland and Virginia chapters of the Coastal Conservation Association, a group of recreational anglers, dumped nearly 150 of them overboard just off the shores of Tilghman Island. They were laid alongside 72 reef balls that were dropped last year.
The project united the anglers with environmentalists, business sponsors and students for a common objective: cleaning the Chesapeake for the sake of its ecology and for its economic power.
The strategy for restoring the bay's oyster population has become divisive in recent years, with debates over where watermen should be allowed to harvest and how much of the shellfish population should be held in sanctuary.
Projects such as the Tilghman Island reef show the industry and science don't have to be at odds, said Del. Robert Flanagan, who joined Schoberg and two Carroll County teachers Wednesday to watch the new reef be built.
"We can have sanctuaries and still have this thriving industry," the Ellicott City Republican said. "We can do both."
The Coastal Conservation Association funded the $20,000 project largely through its Building Conservation Trust, a program that aims to restore or create new habitats for fish and other marine organisms.
It pulled in the support of groups such as the Chesapeake Bay Foundation whose ship, the Patricia Campbell, was used to ferry and drop the reef balls, and companies like Lehigh Heidelberg Cement Group, which supplied the concrete, said David Sikorski, executive director of the association's Maryland chapter.
And they employed the labor of students from across the bay watershed — including a handful of Carroll County schools, the Anne Arundel Center For Applied Technology North, and James Madison High School in Vienna, Va.
About half of the reef balls planted Wednesday were each covered in about 2,000 baby oysters, grown by the bay foundation at its Oyster Restoration Center in Shady Side. That made them already a dingy gray as the ship's crane lowered them into the bay, four at a time.
Students made the reef balls with fiberglass molds developed by Georgia-based nonprofit the Reef Ball Foundation. They mixed the concrete, poured it in the molds and waited for them to set.
Underwater surveys and photos of last year's reef balls show an area of bay bottom that would otherwise be barren sand is teeming with life. They are part of an 84-acre artificial reef that also contains bridge decking, tires and granite, according to the Maryland Artificial Reef Initiative, a program of the state natural resources department.
Allison Sweeney and Bethany Baer, fourth-grade teachers at Elmer Woolfe Elementary School in Union Bridge, said the project came amidst lessons about bay ecology and water quality and about the history of Maryland's seafood industry. The two tagged along Wednesday to snap photos to share with their students.
"In social studies we talk about the job of the bay," Sweeney said. "We talked about how our natural resources affect what we can do in our society."
The lessons stuck with Schober. She remembered seeing pictures of massive piles of oyster shells, from back when there were nearly 100 times more of the bivalves across the bay.
"Now there's just barely any left," she said.
But one of her favorite lessons was about the Chesapeake "Oyster Wars," conflicts in the late 1800s and early 1900s between watermen and pirates who dredged for oysters illegally. That conflict, and the ongoing struggles of watermen on the bay, taught her the economic importance of oyster harvesting.
"You can't say 'don't do it for a month,' because some people make their money that way," Schober said.