One struggling D.C. charter school will shrink at the end of this academic year, another will be acquired by a high-performing school and a third will close if it fails to show improvement over the next several months, the D.C. Public Charter School Board decided Monday.

At the same meeting, the charter board voted unanimously to allow California nonprofit Rocketship Education to open as many as eight schools that would serve 5,200 District students by 2019.

The decisions reflect the board’s efforts to clamp down on low-performing schools while opening doors for charter operators with a record of success.

“Part of the genius of the charter model is it does allow for a certain innovative churn, where you close low performers and thereby create space for new innovators to come in and try new models,” said Brian Jones, the outgoing chairman of the charter board. Board members elected John “Skip” McKoy, who has been the board’s vice chairman, to succeed Jones.

The board authorized Rocketship to open two schools with 650 students each, but the organization could expand to eight schools should existing campuses perform as well as promised.

Rocketship, which relies on a combination of face-to-face instruction and online learning, operates seven schools in San Jose that have won national attention for their success teaching children from low-income backgrounds.

Among the schools to be closed is Septima Clark in Anacostia, the city’s only all-boys public school, which enrolls more than 200 elementary students. Septima’s board of directors proposed that the school be acquired by Achievement Prep, a nearby well-regarded co-ed middle school. On Thursday, the citywide charter board approved that plan.

Most of Septima’s students will be guaranteed a seat at Achievement Prep, which is expanding into the elementary grades. In return, Achievement Prep will assume Septima’s assets, which amount to more than $1 million.

The acquisition is the first of its kind in the District and could be a model for future takeovers as charter officials seek to ease transitions for students in schools slated to close. But it has sparked turmoil at Septima, with founder Jenny DuFresne resigning as the school’s head to protest what she said was a lack of transparency on the part of the board of directors.

Parents also have mounted fierce resistance, saying Septima’s board of directors was acting unfairly, unnecessarily and behind closed doors when it decided to shutter the school.

“We as parents decided that Septima Clark was the best for our boys,” said Ayana Osborne, a mother of two Septima students, who argued that the school had made great strides even with its willingness to accept boys with difficult behavior and other challenging needs.

Septima’s students made larger test score gains last year than any other charter in the city, but only about a third of its students were proficient in math and reading. Such results endangered its long-term prospects and made it difficult to secure a bank loan for a permanent facility, according to Septima’s board of directors.

Jay Costan, Septima’s board chairman, said that he and his colleagues had no choice but to close the school but that he hopes the shift to Achievement Prep will give most of Septima’s boys a pathway to a good school without having to enter a lottery. “We made a commitment to give these boys the best education possible, and when we took a hard look at it, we realized that we weren’t doing that,” Costan said.

Howard Road Academy, another school east of the Anacostia River that was in danger of being closed for poor performance, will instead shrink, shuttering two of its three campuses and giving up grades one through eight to focus solely on early childhood education.

A third school, Imagine Southeast, will need to show significant gains to keep its doors open.

Imagine Southeast, an elementary and middle school enrolling 600 students, is part of a nationwide network of charters operated by Imagine, a for-profit company based in Arlington County.

It had been a candidate for closure because of its failure to meet academic achievement expectations and other goals.

To stave off closure, the school’s leaders agreed to stop serving grades seven and eight and to bring in educators from other Imagine schools who have a record of improving schools. Imagine Southeast also agreed that if it fails to hit achievement benchmarks this year or next, it will turn management of the school over to another charter operator.