The D.C. Education Festival in January 2014 at the Washington Convention Center was a chance for families to learn about charter schools. (Sarah L. Voisin/The Washington Post)

The D.C. Public Charter School Board approved three new charter schools this week, including an all-boys middle school and an adult education campus.

The new schools will add hundreds of charter-school seats to the city, the majority of them for middle school students.

The charter sector enrolls about 46 percent of D.C.’s public education students, but enrollment in charters surpasses traditional public schools in most middle school grades.

The board on Monday approved the opening of Digital Pioneers Academy, a computer-science-focused middle school that will be in Ward 7 or Ward 8. The school is slated to open in the 2018-2019 school year.

“We’re excited to bring a new, innovative model to the District and play a part in making Wards 7 and 8 a model of quality education,” said Mashea Ashton, the school’s founder.

North Star College Preparatory Academy for Boys, a college-preparatory middle school, will also open in Ward 7 or 8 in 2018.

Charter schools have benefited from growing demand for middle school seats. About 54 percent of the city’s public-school sixth-graders enrolled in charters this year. A decade ago, 30 percent of D.C. sixth-graders were in charters.

The board’s approval of the new schools will initially create 205 new middle school seats. The schools plan to expand in subsequent years.

“We’re pleased to approve three schools that will meet the needs of our diverse student community,” said Darren Woodruff, chairman of the charter board. “This was a rigorous process with a high standard of approval.”

The charter board also approved the opening of the Family Place, an adult school in Ward 1 that will educate 120 students in its first year.

It will offer English as a second language, workforce training and literacy development education to low-income adults who have limited English proficiency.