The head of the Newark school system is calling for the closure of four local charter schools and a ban on most new charter schools, a clear signal that the district hopes to rein in the city’s fast-growing charter sector.

The schools — M.E.T.S., People’s Prep, Roseville Community, and University Heights — are up for renewal, meaning they must apply for state approval to continue operating after this academic year. In a series of letters this month, Newark Public Schools Superintendent Roger León asked the state to reject their applications, arguing that the publicly funded, privately managed charter schools sap funding from traditional public schools and are failing to serve their fair share of students with special needs.

The state education commissioner is expected to make a decision by Feb. 1.

León also urged the state to deny “any and all” applications for new charter schools or the renewal of existing charter schools unless they serve “a specific educational need.” While other local officials have sought to halt the expansion of Newark’s charter sector, whose student population quadrupled over the past decade, León is taking a more extreme position by demanding that existing charter schools be phased out.

“The writing is on the wall for corporate charter schools,” said Newark Teachers Union President John Abeigon, an outspoken critic of charter schools, which tend to be non-unionized. “The days of unchecked charter school applications are over.”

León, who spent his entire career working in Newark Public Schools before becoming superintendent last year, has walked a fine line when it comes to charter schools, which enjoy significant public and political support in the city.

He has publicly praised some high-performing charters and sought to preserve the city’s common application system for traditional and charter schools. Yet he has also made clear his desire to draw more families back into district schools, and expressed alarm at the swelling share of tax dollars funneled to Newark’s charter schools, which educate more than a third of the city’s public-school students.

León’s letters to the state — including one implying that he plans to eject a charter school from a district building — remove any doubt that he intends to use all the means at his disposal to staunch the flow of students and funding to the city’s charter sector.

Some charter school leaders, who have already accused León’s administration of trying to limit families’ access to charter schools, view his new stance as an open attack.

“The call to close all four schools is reckless and does not take into consideration what’s best for students and families,” said Harry Lee, president and CEO of the New Jersey Charter Schools Association. “This was surprising and an aggressive move by the district.”

During the periodic charter renewal process, which all New Jersey charter schools undergo, the state education department visits the schools, conducts interviews, and reviews each school’s application, academic data, and financial records. The department must also consider the recommendation of the local traditional school board, according to state regulations. León’s letters are not signed by Newark’s board, but a state spokesperson said the department will consider all relevant records during the review process.

León raised a number of general objections in his letters to Lamont Repollet, the education commissioner.

First, he cited the financial impact of charter schools on the district. Because school aid follows students in New Jersey, districts must hand over most of the funding attached to each student who enrolls in a charter school. (Districts keep a small portion of that funding to cover expenses such as building maintenance that remain constant even when students opt out of the district.) This year, about 30% of the district’s revenue was redirected to charter schools, León said.

“As that budget is barely sufficient to meet the district’s needs,” he wrote, “the impact of such a large payment stream cannot be [overstated].”

Second, he suggested that the schools do not offer students a better education than they could receive in the district. He cited data showing that the district, on average, outperformed all the schools except People’s Prep on state tests in terms of the percentage of students who met grade-level expectations, students’ year-over-year improvement, or both.

Finally, he questioned whether the schools adequately serve a significant number of students with special needs. He pointed to data in the schools’ renewal applications showing that they serve a smaller share of students with disabilities or those still learning English than the district, and argued that the schools’ own descriptions of their programs suggest students are not being properly served.

“Data in the renewal application shows that the school currently fails to address the educational needs of Newark’s most vulnerable students,” he wrote in each letter.

León added a few specific objections. He noted that the state put M.E.T.S. and University Heights on probation this year due to poor performance and safety concerns. He also accused People’s Prep of enrolling more students than it is authorized to serve, admitting students regardless of their order on a district-made waiting list, and exceeding its allotted space in the part of a district building it rents. The letter says People’s Prep will “likely need to vacate” the building, which it shares with Bard Early College High School, after its lease expires in June.

The heads of People’s Prep, M.E.T.S., and University Heights did not immediately respond to emails. A district spokesperson also did not respond to a request for comment.

Lee pushed back on several of León’s claims, arguing for instance that the district controls the common enrollment system and could send more students with special needs to charter schools if it chose to.

In an interview, the leaders of Roseville Community Charter School defended the school, which enrolls students in kindergarten through fourth grade in Newark’s North Ward.

They said Roseville serves a sizable share of students with special needs — this year, 15.5% have disabilities and 18.4% are still learning English — which is comparable to Newark Public Schools, where each group accounts for 17% of students. The school has also expanded its services for those students, including by hiring additional staffers, despite the district poaching one of its English-language teachers in September, they added.

“It appears the leadership of Newark Public Schools is seriously misinformed and misguided,” said Rashon Hasan, the chair of Roseville’s board of trustees, adding that León has not visited the school. Shutting down the school would be “devastating for families,” he added.

Dionne Ledford, Roseville’s principal and executive director, said a group of parents sent their own letter imploring the state to keep the school open.

“It’s a true community school,” she said. “A true family.”

León’s letters to the state are below.