The parents knew M.S. 61’s building in Crown Heights was getting a close look as the city hunted for space for Launch Expeditionary Learning Charter School, one of four charter schools the city has committed to finding space for under a new state law. In matching M.S. 61 T-shirts, they told Fariña they wanted nothing to do it.

One week later, Fariña told them she had heard their concerns.

“We’re not going to put a charter school in this building,” Fariña announced to an auditorium full of parents Wednesday night before being drowned out by applause.

The decision underscores how seriously the new administration is taking the concerns of school communities, and signifies that the Department of Education is less willing than in years past to pick fights with district schools to accommodate charter schools. It also illustrates how tricky it will be for officials to come up with space-sharing arrangements for new charter schools that are now guaranteed access to city facilities (or city funding), since few schools are eager for the complications that come with sharing space.

While Fariña didn’t explain the city’s decision making process, she indicated that she had listened to the parents and teachers of M.S. 61, who called their lobbying effort a success. That culminated last week at Murry Bergtraum High School, where Fariña was meeting with the Panel for Educational Policy. At the meeting, the parents held signs, spoke of their school’s desire to expand, and declared their opposition to sharing space with Launch Expeditionary, which will add high-school grades in the 2015-16 year.

“We need to remain one school in one building in order to see our vision completed,” said Karone Playfair, M.S. 61’s parent association president.

M.S. 61 currently uses up just over 50 percent of its building, and last year’s enrollment of 777 students is the lowest it’s been in the last two decades, according to city data. But Playfair said that its enrollment is low because it has been capped by the Department of Education. (There were 810 applications for 203 spots open in M.S. 61’s three programs last year, according to data obtained by DNAinfo.)

The middle school, which includes a gifted and talented program, is made up entirely of students who qualify for free or reduced lunch and 98 percent of students are black or Hispanic. Sixteen percent of students were proficient on last year’s math tests and 19 percent were proficient on the English tests, both below district averages.

Shannon Burton, who is in his second year as principal, said he’s added courses and that he’s already seeing more demand for the school. On Wednesday, he said he had urged city officials to give the school time to add students and improve.

“Give us one more year,” Burton said. “I’ll be at the right numbers.”

Last week, a working group appointed by the mayor released a list of recommendations for the city to consider as it revamps its policies for co-locating schools, a practice that has often left schools fighting over access to common facilities like gyms and cafeterias. One of the group’s top recommendations was for the city to be more transparent with existing schools about possible co-location plans.

Playfair said that an education department official first informed the school that a co-location was possible on Oct. 7 as he toured the building with parents and the school leadership team. But the parents grew increasingly worried when they learned that the same official had visited the school unannounced on three subsequent occasions to view space in the basement.

“You can come in, but what are you doing sneaking around?” Burton said.

On Wednesday, district superintendent Clarence Ellis said he wasn’t sure why the city backed off its pursuit of the space, and Fariña did not stick around after the town hall to discuss the issue. School officials are now discussing how to use the extra building space for other purposes, he said.

“If the principal here can up his numbers, if he goes out and parents want to bring their kids here because neighbors are saying good things are happening here, I’m encouraging that,” Ellis said.

Fariña still faces the complicated task of accommodating the space needs of district and now some charter schools. At the meeting, she also offered perhaps her most ardent public defense of charter schools yet, along with a challenge to traditional public schools.

“As long as parents choose to send their kids to charter schools, because it is parent choice, there is always going to be a need for them,” Fariña said. “And I am not going to say what parents should choose to do. However, I will say that public schools need to be a little bit more competitive. I’m urging principals not to focus on what other people are doing, but what can I do to make this school the best school possible and how do I get the word out there.”