D.C. Public Schools Chancellor Kaya Henderson speaks during a news conference in June at Leckie Elementary School. (Jabin Botsford/The Washington Post)

D.C. Public Schools Chancellor Kaya Henderson focused on signs of progress during her third­ annual State of the Schools event Wednesday night, including a recently released uptick in graduation rates, new investments in electives and college-level classes in the city’s high schools, and more engaging courses systemwide.

She also addressed some of the challenges she has faced in building a workforce, as she pushes for progress in an urban school system that aims to be a national leader in education reform. In a conversation with Channel 4 news anchor Jim Vance at Dunbar High School, she talked about high rates of teacher turnover and the declining number of African American teachers in the system.

“Everybody romanticizes what it means to teach in an under­resourced urban public school system,” she said. “Sometimes the reality does not match up with their expectations.”

The city’s public school system is growing at a steady pace. It is projected to enroll more than 49,000 students this year, a fifth year of increases after more than a decade of declines. It also opened four schools after two major rounds of school closings in seven years. To keep up, the District added about 250 positions this year and hired 789 teachers.

Vance asked Henderson what happened to the 500 or so teachers who left their jobs. “Experience is a valuable thing,” Vance said.

Henderson said that some of those teachers were promoted and others left because they or the school system decided that the job was not a good fit. She noted that the school district retains 92 percent of its highly effective teachers, and that, while many districts are facing teacher shortages, the District has not had trouble recruiting new talent.

“Instead of being a district of last resort, we are now a place where teachers want to come,” she said.

High turnover has been a major source of criticism for the school system since former chancellor Michelle Rhee negotiated a new contract with the union. That contract included the ability to fire teachers — or give them significant raises — based on performance evaluations, something that has been historically rare across the country. Principals’ employment is also contingent on annual evaluations.

A recent report funded by the American Federation of Teachers found that the share of black teachers in the District decreased from 77 percent to 49 percent while the white workforce more than doubled from 16 percent to 39 percent. Vance asked Henderson how she felt about the significant decline in African American teachers.

“My first priority is getting great teachers no matter what color they are,” Henderson said, noting that she did not know all the reasons for the decline. “We fired some people, I’ll be honest with you. But we didn’t just fire black teachers; we fired teachers of all stripes.”

The school system is increasing its focus on the specific challenges faced by boys through its Empowering Males of Color Initiative. Henderson said that she would like to bring more African American and Latino male teachers into classrooms, but she said there is a limited pool of qualified applicants.

The report from the AFT cited research showing that minority students who work with a teacher of their same race tend to do better academically.

Elizabeth Davis, president of the Washington Teacher’s Union, said Henderson’s response to the decline in minority teachers was unsatisfying.

“What is the plan for changing those percentages?” Davis said. “What are you going to do to ensure that we do have a diverse teaching workforce?”

According to data released by D.C. Public Schools this fall, overall applications for teaching jobs increased this year, but the share of new hires that are African American remains below the district average.

In all, 1,590 people applied for 789 new jobs this year, compared with about 1,476 applications for 563 jobs in 2013. Of new hires, 42 percent were African American, compared with 47 percent District-wide.

At the same time, 37 percent of new teachers hired were white, compared with 32 percent District­-wide. Eight percent of new teachers are Latino, compared with 5 percent of all teachers.

The applicant pool for principal positions also grew this year, with 337 contenders for 29 positions, compared with 234 applications for 25 positions in 2013.

The vast majority of new principals — 69 percent — are black, compared with 62 percent of all principals.

During her remarks, Henderson also addressed turnover among principals.

One in four schools started the year with a new principal, which concerns many teachers and parents who say stability at the top is fundamental to building momentum and community at a school.

“Churn or turnover in and of itself is not a bad thing,” Henderson said. The job is changing, and the school district is finding some success in training its own leaders through a new fellowship program, she said.

One thing that the program teaches leaders is how to support, develop and retain a staff. Henderson said officials consider their principals’ teacher retention rates during annual evaluations.

“If every year you are replacing a third of your staff, something is wrong,” she said. “We look at that, we have conversations. . . . Or if they are not the right leader for DCPS, they move on.”