Some students in Sunset Park posted signs on their school’s windows during a shelter-in-place order after Tuesday’s nearby mass subway shooting — with one note pleading, “Make NYC Safe Again.”

A shooter opened fire in a train car at the 36th Street station in Sunset Park during the morning rush, injuring 29 people. The shooting led schools in the area to shelter-in-place for at least several hours.

Some local schools — PS 24, Sunset Park High School, PS 371 and two locations of Little Brooklyn Pre-K Center — kept their doors shut until dismissal.

The photo of the kids’ signs was tweeted out by a local journalist and included another handwritten message urging, “Have Hope NYC” followed by a heart.

Additional police and school-safety agents were stationed at schools for dismissal, according to the city Department of Education, and shuttle buses transported students to subway stations.

Some extracurriculars and sports were subject to cancellation, too, a department rep said.

Parents from District 15, which includes Sunset Park and also extends to some of Brooklyn’s wealthiest neighborhoods such as Park Slope and Carroll Gardens, met with DOE staff at a meeting Tuesday night.

“Some of our children were on that train,” said Camille Casaretti, president of the district’s Community Education Council, an advisory group comprised of mostly parents. “Our community is going to need a lot of support.”

The department’s security director, Mark Rampersant, told families there was no plan to shelter-in schools tomorrow — but that students can expect “we’re going to show them love” and school safety agents will be available to do “temperature checks.”

“We are working closely with NYPD and school leadership to ensure that every school has the supports they need as we work to ensure the safety of our school communities,” said schools Chancellor David Banks in a statement.

“My thoughts go out to the victims of this tragedy,” he said.