The science lab at Key Elementary School in Northwest Washington, DC, buzzed with energy as the fourth graders hunched over tables. They peered into Petri dishes at the tiny, pearl-shaped blobs floating in them. Carefully, they wielded eyedroppers to separate the clear ones from those that appeared cloudy.

Then, someone gasped.

“Something popped out!” one youngster exclaimed. “It’s alive!”

First one, then another and another of the clear American shad eggs in the Petri dishes hatched into tiny fry, wriggling about in the water as classmates clamored to see.

Thus, members of a new human generation, many of whom had never heard of shad before this year, met the offspring of what was once one of the Chesapeake Bay’s most celebrated fish, now struggling back from the brink of oblivion.

Aden Smith (left) and Charlie Conroy watch as Aleksandrs Jekabsons sorts fertilized shad eggs from the ‘duds,’ under the supervision of science teacher Amy Johnson. (Dave Harp)For more than 20 years now, District area schoolchildren have been helping to bring shad back through a hands-on learning experience that teaches them about the fishes’ historic importance, its near-disappearance from the Bay and its remarkable recovery, at least in the Potomac River.

With help from some dedicated adults and a shifting cast of nonprofit groups and government agencies, youngsters in dozens of schools tend to shad eggs in small classroom hatcheries for about a week. Once the eggs hatch, they release the fry into the Potomac and its tributaries. In the process, the kids absorb lessons about human and natural history, biology, ecology and the conservation ethic.

“It goes a long way,” said Jim Cummins, a biologist recently retired from the Interstate Commission on the Potomac River Basin, who with others launched the “Schools in Schools” initiative, as it’s known. “I think it helps build their understanding of the Bay and the river, and the restoration process. It gives them some buy-in.”

Shad need all of the help they can get. Once so plentiful that they heralded spring’s arrival with massive silvery spawning runs up the Bay’s rivers, the migratory fish fell victim to overfishing, pollution and dams blocking them from their spawning grounds. By the early 1980s they had become so scarce that fishing for them was banned Baywide, a prohibition that remains in effect.

It was a tragic decline for what has been called America’s “founding fish.” George Washington ate them, as did legions of others. Fishermen from one end of the Bay to the other landed them by the hundreds and even thousands with each cast of their nets. In the 1830s, horse-drawn wagons jammed Georgetown streets near the canal to pick up barrel-loads of the salted fish, according to a newspaper account.

Today, the tasty but bony fish that once graced many a spring table in the Chesapeake region is missing from restaurant menus and seafood markets. It’s largely forgotten, except among dedicated anglers. “Anybody under 65 years of age doesn’t know what they are,” said Cummins, himself 65.

That’s starting to change, at least in the DC area. While shad runs remain anemic in the Susquehanna River and several other Bay tributaries, they have rebounded strongly in the Potomac. Key to the recovery was the construction in 2000 of a fishway through a dam at Little Falls, reopening 10 miles of river that had long been denied to spawning shad. Meanwhile, the natural reproduction got a boost with annual stockings from the mid-1990s through 2014 with around 22 million shad fry reared at hatcheries.

Key Elementary School fourth graders Irby Thompson, left, and Charlie Conroy use droppers to separate fertilized shad eggs from unfertilized ones. (Dave Harp)The Potomac commission launched the shad initiative for students in their belief that public support would be crucial to persuade policy makers to open the purse strings for the Little Falls fish passage and the rest of the shad restoration effort. So, they invited a group of students to witness the first stocking, and the next year to lend a hand.

What started out in 1996 with three schools grew at one point to involve more than 50 across the metropolitan area. Tens of thousands of students have participated since it began, releasing nearly 400,000 fry into the Potomac and its tributaries, according to a report prepared by Cummins just before he retired last year.

The effort has scaled back some, and coordination of the shad egg collection, hatching in classrooms and release has passed from one nonprofit to another as funding has waxed and waned. This year, 1,360 students in 28 schools got involved, releasing 24,500 shad fry, according to Chris Lemieux, education manager for the Anacostia Watershed Society, which handles the program now.

The enthusiasm of those involved is undimmed. This year was Key science teacher Amy Johnson’s first in the shad-rearing project, and she confessed she was “super-excited.” She engaged 54 fourth graders in the effort from three different classes she teaches. They had to assemble a rudimentary mini-hatchery in her lab: a plastic bin atop a 32-gallon trash can, with an aquarium pump and filter to circulate the water via a plastic hose. Then they had to get the water temperature and quality just right. On a warm Sunday afternoon in late April, Johnson joined a few other teachers in a watershed society skiff for a bumpy, soaking ride down the Anacostia and the Potomac to around Mount Vernon, where George Washington once fished for shad. There, they watched as commercial fishermen set nets in the river and hauled in dozens of shad and other fish, a permitted exception to the catch moratorium.

Then, a biologist squeezed eggs from the female shad into a stainless-steel bowl. He got some sperm in a similar manner from the smaller male fish, and finally triggered fertilization by adding a little river water. The fecund mixture got parceled out the next morning to each of the participating schools, where students spent the next few days monitoring water quality and temperature, separating the fertilized eggs from the “duds,” and waiting for them to hatch.

Key Elementary students release the shad fry they raised into the Anacoastia River. (Timothy B. Wheeler)By week’s end, all of the fertilized eggs had “popped out” that were going to, and the Key students and teachers set out by bus for Anacostia Park, to release their fry into the Anacostia. Like shad, it has been dubbed the “forgotten” river because of its severe degradation over the years. Also like the shad, it’s starting to respond to a cleanup and restoration campaign.

“I never knew about shad before,” said 9-year-old Carter Freeman, one of Johnson’s students, as he and classmates prepared to pour plastic cups of water holding shad fry into the murky river. “Now, we’re really happy because the shad are coming back. And the population is increasing again.”

Many of the tiny shad won’t survive, as other fish, osprey and eagles will gobble them up. Those that live will swim downriver, through the Bay and out into the Atlantic Ocean, where they’ll spend four to six years growing and roaming offshore from Canada to Florida. Once they mature, they’ll swim back up the Bay to the river where they were released for their first spawn.

“You’re stocking them to imprint [the river on] them, and they return,” Cummins said of the fish.

But the same is true with the children, he said. “We’ve had several of the students come back,” he added, to witness subsequent releases. Over the years, some also have gone on to studies and careers in biology or environmental science.

“For some of them,” he said, “it’s their moment that they remember.”