Schools Chancellor Carmen Fariña is making good on her promise to consolidate the city’s smallest and lowest-performing schools.

The city Department of Education is proposing a school merger that will fold the tiny P.S. 241 STEM Institute of Manhattan into P.S. 76 A. Philip Randolph, about eight blocks away in Harlem.

If the plan moves ahead, it will end STEM Institute’s long fight to keep its doors open as enrollment at the elementary school has hovered around 100 students. It could also play into a contentious battle to redraw school boundaries on the Upper West Side.

The STEM Institute has struggled on state tests, with only 8 percent of students scoring proficient in math last year. It serves a high-needs population: almost 40 percent of students have disabilities. The school has also had difficulty attracting students, even after landing a multi-million dollar federal grant in 2010 to start a magnet program focusing on science, technology, engineering and math.

P.S. 76’s state test results are comparable to STEM’s. But its enrollment was five times higher last year, and the school has its own building — unlike STEM, which shares its space with two charter schools.

Chancellor Fariña has embraced consolidations as a way to save money on staffing and spend more on services for students. Department spokeswoman Devora Kaye said the consolidation would allow more students to benefit from P.S. 76’s partnership with the Harlem Children’s Zone, and lead to more arts programming for students and more training for teachers.

But the merger plan is also an acknowledgement that the high-profile magnet grant — and some small enrollment gains in recent years — weren’t enough to keep STEM Institute afloat. Kaye said that school’s curriculum would transfer to P.S. 76.

The district superintendent has begun meetings with staff at both schools, and parents will be informed of the proposal on Tuesday, Kaye said in an email. The merger will also require approval from the Panel for Educational Policy.

“Each school consolidation involves an individualized approach,” Kaye wrote. “The goal is always to provide a strong learning environment and expanded resources to best serve all students.”

The news comes at the tail end of a separate rezoning process that has dragged on for more than a year in District 3, which encompasses the Upper West Side and a portion of Harlem. Families, school leaders and the Community Education Council have debated the best way to redraw zone lines to reduce overcrowding and boost student diversity at a handful of schools in the district’s southern end.

So far, none of those proposals affect schools north of 110th Street.

With the merger now on the table, CEC President Joe Fiordaliso said the city should rework those rezoning plans to include the STEM Institute.

“Parents for [P.S.] 241 need and deserve to know where their children will be zoned,” he said.

That would be an extraordinarily tight timeline for engagement with families further uptown, given that the city is expected to present a final draft proposal for the Upper West Side’s rezoning on Wednesday and the CEC is scheduled to cast an up-or-down vote on Nov. 9.

Kaye said the department would “work with the CEC to address zoning issues raised by this potential consolidation.” City planning officials have indicated at recent meetings that they do not want to delay a decision on the Upper West Side plan.

As students lined up to buy after-school empanadas on Monday, a handful of parents said they had not heard about the possibility of a merger between the STEM Institute and P.S. 76.

One parent, Luis Diaz, said he had been impressed with STEM Institute, especially a partnership with a local community center that offers tutoring.

“So far, the school has been good,” said Diaz, who has two daughters at the school.