Although it has kept a lower profile in the past few years, the charter school sector — propelled by an expensive marketing blitz by the three big anti-union charter chains — has continued to grow in New York City.

This year, the legal cap for New York City was reached. While the charter lobby is pushing Albany to raise the cap, public school communities are saying enough is enough.

In the 2015–16 school year, schools operating under 205 charters enrolled 95,000 students, according to the New York City Charter School Center. Today, just three years later, schools operating under 235 charters enroll nearly 119,000 students. Twelve percent of the city’s more than 1 million students attend charter schools this year.

UFT President Michael Mulgrew warned that the New York City school system may be reaching a tipping point if Albany does not check the growth of charter schools.

“We are already losing almost $2.1 billion a year in city funding, money that would make a huge difference for our students and our school system,” Mulgrew said. “Charter schools are not accountable for how they spend public funds and continue to push out students with the greatest needs. We cannot allow our schools to be decimated by a charter system that fails to serve all children and refuses to be transparent about their operations.”

While two community school districts — District 20 in Brooklyn and District 26 in Queens — have no charter schools at all, other districts are fast reaching a saturation point [see map]. Charter schools now enroll roughly half the students in two school districts — District 5 in Harlem and District 16 in Bedford-Stuyvesant, Brooklyn — and more than a third of the students in three other districts — District 4 in East Harlem, District 7 in the South Bronx and District 23 in Brownsville, Brooklyn — attend charter schools.

Even if the cap remains, New York City charter enrollment will continue to expand in the years ahead as charter schools add grades under their existing charters. In addition to phasing in a new school grade by grade, charter chains are maneuvering to squeeze more seats out of each charter: A charter operator who receives a charter to open a grades K–5 school can eventually introduce a middle school and a high school.

Although New York City has issued 235 charters since 1999, there are actually 377 charter schools in operation if elementary, middle and high school divisions are counted separately, according to a UFT analysis.

New York State Senate Education Chair Shelley Mayer has introduced legislation (S.5950) that would close the loophole that allows a single charter license to expand into three new charter schools and legislation (S.5978) that would require greater community consent when oversaturation of charter schools becomes an issue.

Her bills join legislation (S.4237) introduced by Sen. Brad Hoylman to demand greater accountability and transparency from the charter sector and legislation (S.6043) from Sen. John Liu, the chair of the Senate subcommittee on New York City education, to end the use of public funds to pay for private facility space for charter schools.

Teachers in public schools co-located with charter schools worry about the emergence of a parallel school system, with a huge marketing budget but no genuine interest in serving all students, if charter growth continues unabated.

Jason Varon is a physical education and health teacher and chapter leader at MS 354, which occupies the third floor of its Crown Heights school building, sandwiched between a KIPP elementary (second floor) and middle school (fourth floor).

Varon fears public schools like his, which don’t have advertising firms highlighting their accomplishments, will not be able to compete against slick charter ad campaigns. “Charters put a lot of money into marketing,” he said. “They have more reach and ability to advertise. I’ve seen their signs on the sides of buses.”

Miari Roberts is a special education teacher at Brooklyn Academy HS in Bedford-Stuyvesant, a transfer school serving students ages 16–21 that is co-located with two Uncommon Charter Schools, a middle school and a high school.

Roberts fears that Uncommon Charter Schools will squeeze out her high school altogether, leaving few options for her at-risk students who are not welcome in most charter schools.

She also expressed concern about the lack of oversight of charter operations. “We don’t know the ins and outs of how they discipline and suspend students,” she said. “Some of our students were in charter schools, and many of them have IEPs. In a public school, every student has to be taken care of.”

Roberts lives in District 14, which encompasses parts of Bushwick, Williamsburg and Greenpoint in Brooklyn. Her son attends a public middle school there.

“I get the charter mailings at home,” Roberts said. “It is intense and constant.”