One in six primary schools are now serving up fish which has come from sustainable sources, a report from the Marine Stewardship Council (MSC) has revealed.
Seafood school dinners ranging from pollack and mushy pea fish fingers to tortilla nacho fish fillets or tempura battered salmon and sweet potato fishcakes are on the menu at 2,874 primary schools which are now certified as providing sustainable fish.
Some 572 schools, of which 458 are primaries, have become MSC certified in the past year, an 18% increase which the council puts down to new school food standards which came into force in January.
The standards, part of the School Food Plan, require schools to serve oily fish, such as salmon or mackerel, every three weeks and recommend sourcing fish certified as sustainable by the MSC.
There are now 2,874 primary schools which are certified as serving sustainable fish, or 17%, and a total of 3,741 schools across all ages are certified.
The MSC's "end of term report" for 2015 revealed the South East, which had lagged behind last year, has improved significantly, with 209 schools becoming certified under the council's scheme.
The Midlands, which had already been doing well, added another 164 certified schools, while the South West which had no certified schools until late 2014 despite having three MSC sustainable fisheries, now has 47 signed-up schools.
More than 3,000 schools have joined the council's "Kids and Fish" programme which also teaches children about the marine environment and fisheries.
There was also a 33% increase in sales of MSC certified fish into the education sector, the council said.
Henry Dimbleby, one of the authors of the school food standards, said: "This report highlights the impact of the School Food Plan on the sourcing of fish in schools.
"It shows a strong start, though there is still a long way to go.
"Thousands more school pupils eating sustainable fish, supporting sustainable fishing and learning how to protect the marine environment: That's a fantastic legacy to leave our children."
Toby Middleton, programme director at the MSC, said: "We've seen a significant increase in schools serving MSC certified fish and a renewed interest in oily fish.
"Under the school food standards, schools are required to serve oily fish every three weeks and they recommend MSC certified fish.
"With the standards coming into force in January we've seen renewed commitments from local education authorities and their suppliers coupled with a real shift in attitudes toward sustainable fish sourcing."