Invasive blue catfish are a problem in the Chesapeake Bay and its tributaries, preying on native seafood like the blue crab. To help keep them in check, local schoolchildren are eating catfish for lunch. Ryan Kellman/NPR hide caption

Ryan Kellman/NPR

PRESTON, Md. — It's lunchtime at Preston Elementary School, on Maryland's Eastern Shore. Kids file in, get dollops of food on their segmented trays, and maybe grab a chocolate milk. But one option on today's menu is special, served alongside grapes and broccoli.

"I got a catfish sandwich!" announces Ben Rochon, a second-grader. Between mouthfuls, he tells me how it is: "It's yummy."

He's eating a catfish cake, also known by its nickname, the "catty patty." Some kids like it with ketchup or mayo. Fifth-grader Teagan Donovan goes minimal.

"I like it by itself with no toppings, because it's pretty good by itself," she says.…