Authorities are looking into a grade-fixing scandal at a city high school that boasts a near-perfect graduation rate, the Queens District Attorney’s Office said Monday.

The stunning allegations involving Maspeth HS — revealed in a front-page Post expose Sunday — are “under review by our Public Integrity Bureau,” a spokesperson for acting DA John Ryan said.

As of Monday, seven teachers have told The Post they were pressured to pass undeserving students as part of an unwritten school policy that kids call the “Maspeth Minimum.”

The no-fail directive allegedly allowed 99% of kids to graduate in four years in 2018, the latest year for which data is available, and led US Education Secretary Betsy DeVos to name Mapseth a National Blue Ribbon School the same year.

Ryan learned about the alleged scam from city Councilman Robert Holden (D-Queens), who shared the teachers’ claims during an hour-long meeting at Queens Borough Hall on Friday, according to a source familiar with the matter.

Holden on Monday told The Post that he would “go even further if this is not investigated.”

“The people responsible for much of this should be identified and I would like to see them prosecuted,” he said.

Holden also ripped a decision by Anastasia Coleman, the special commissioner of investigation for the city’s schools, to refer the matter to the Department of Education’s Office of Special Investigations after he sent her an Aug. 7 letter outlining the whistle-blowers’ “mountain of evidence.”

“I don’t like that they’re in charge of their own probe into grade fraud,” he said of the DOE.

DOE spokeswoman Danielle Filson said, “When the Special Commissioner refers allegations to the DOE’s Office of Special Investigations, it conducts full, fair and impartial investigations. This will be no different.”

Some Maspeth High students were outraged to learn about the alleged grade inflation.

“That’s BS,” said a 14-year-old freshman who gave his name as Charlie.

“It’s unfair for the students that work hard because others are just going to get a free ride to graduation. Meanwhile, we’re studying hard.”