Andria Caruthers, principal at West Education Campus, goes door to door to recruit students for enrollment last month, part of a D.C. public school system push to sell the city’s schools to families. (Marvin Joseph/The Washington Post)

The District’s traditional public school system is sending principals out to knock on doors in a campaign to sell itself to city families, an aggressive move to boost enrollment and maintain market share after years of ceding ground to charter schools.

The move is a sign of the tremendous pressure on the District’s traditional public schools. Charter schools, which appeared less than two decades ago, now enroll nearly half the city’s public school students, and they continue to gain popularity. It is a trend that many believe threatens the long-term survival of the traditional school system.

To train principals in old-fashioned door-to-door canvassing, school officials have hired political campaign experts who helped Barack Obama win the presidency. These experts are also adapting data-analytic methods used to target voters in 2008 and 2012 to help identify those students most likely to bolt the school system and, therefore, most in need of personal attention.

“I’ve got to keep my school open and growing,” said Principal Kennard Branch of Southeast Washington’s Garfield Elementary, one of about 30 principals who left recent student-recruitment training sessions with plans to knock on hundreds of doors during the first weeks of summer.

In the waning days of the school year, these experienced educators found themselves assembling teams of volunteer door-knockers and tinkering with fliers meant to encourage parents to consider their schools. They also refined the sales pitch for those parents who had decided to send their children elsewhere.

Michele Gassaway, Anthony Gaines and Tyronica Williams enroll their children in school at a DC Public Schools-sponsored enrollment carnival at Garfield Elementary in Washington. (Linda Davidson/The Washington Post)

“I know you said you committed to a charter school,” said Principal Andria Caruthers of West Education Campus, demonstrating for her team of volunteers how one might engage a family that appears determined to leave the school system. “I’m asking you, can you stop by the school tomorrow?”

Gone are the days when public schools could sit back and wait for students to show up on the first day of class. In this era of school choice, families have become consumers, and educators have become marketers as responsible for selling their academic offerings as they are for teaching and learning.

Nowhere is that shift more apparent than in the District, home to one of the most crowded and competitive school marketplaces in the nation, where a school’s budget — and continued existence — depends on the number of students it manages to enroll.

“We know that we have to fight for our students and win over hearts and minds because there are so many great choices out there,” said Christopher Rinkus, who oversees the school system’s enrollment efforts. “There’s a mind-set we’re working to change, that enrollment happens when it happens. . . . We’re in a climate where you can’t afford that mind-set.”

From 1996 to 2012, enrollment in the city’s traditional schools declined from about 75,000 to about 45,000. Although enrollment ticked up slightly in 2013, the school system still lost market share to charters, which now enroll 36,500 students, or 44 percent of the city’s public school population. Charter schools in the District educate a higher percentage of local students than anywhere in the United States other than Detroit and New Orleans, where traditional schools have been replaced almost entirely by charters.

Across the country, wherever charter schools have taken root, they are known for marketing themselves aggressively. Advocates for school choice, a philosophy that the Obama administration has embraced, say charter schools are forcing traditional school systems to think of families as customers.

“It means we’ve done our jobs,” said Kara Kerwin of the Center for Education Reform, a pro-charter advocacy organization.

But others say marketing efforts such as the District’s beg important questions about the unintended consequences of school choice, including whether the push to sell schools distracts from the goal of improving instruction.

“At a time of very limited school resources, do we want our resources diverted to marketing?” said Kevin Welner, director of the National Education Policy Center at the University of Colorado at Boulder. “We ask a lot of our principals. . . . Is door-to-door solicitation what we really want them to be doing?”

Some D.C. principals agree. “If you run a good program, parents will know. Word of mouth is very powerful,” said one principal, who spoke on the condition of anonymity to avoid antagonizing supervisors.

Many principals in the District feel a responsibility to do whatever they can to boost enrollment. More students mean additional staff and resources that can help a principal build attractive programs.

“I don’t think I allow myself to go down the road of ‘Is it a good use of my time?’ ” said Caruthers, the principal of West, a K-8 school in Northwest Washington’s 16th Street Heights neighborhood. “I think it’s a reality of where we’re at in education right now.”

D.C. school leaders were trained in campaign-style recruitment techniques in late May and early June. Leading the sessions was 270 Strategies, a firm founded by two political insiders known for combining data analytics and massive grass-roots organizing to help elect and reelect the nation’s first black president. The second time around, in 2012, Mitch Stewart was Obama’s battleground states director, and Jeremy Bird was his national field director.

The school system paid $14,000 for five two-hour training sessions to introduce principals to the art of door-to-door canvassing. Jesse Boateng, director of Florida voter registration for Obama’s 2012 campaign, led the sessions, sharing tips from the campaign trail: Don’t spend more than five minutes at any one door, and if you‘re having trouble reaching a targeted family, go back but not more than five times.

“You’re delivering a very specific message and asking a very specific question to capture data,” Boateng said. “Canvassing is one of the most efficient campaign strategies ever. We know that.”

Boateng left principals with a sample door-knocking script, templates for marketing literature and spreadsheets for recording which families were contacted and how they responded. He pushed principals to focus on “the lowest-hanging fruit,” persuading the families of current students, who must re-enroll every year in the District, to fill out the paperwork.

The firm is analyzing five years of student data to create a model for identifying the students most likely to leave. The school system is paying $30,000 for that work, and officials hope the model will be ready in time to help principals plan their recruitment efforts next spring.

“Once we’ve managed to figure out how we get our kids to return to our schools, we can figure out how to market to new families,” said Rinkus, whose job is to ensure that the school system hits its enrollment target of 47,592 students in the fall, an increase of more than 1,000 students from the 2013-2014 school year.

Hari Sevugan, a spokesman for 270 Strategies, declined to say whether the firm gave D.C. schools a discount. He said the firm does not comment on contracts with clients.

Going through the city’s neighborhoods, some principals found themselves knocking on doors without getting a response. Others said that appearing on students’ doorsteps seemed to open the way for a stronger connection with families. Still others said they were welcomed by parents who had intended to enroll but hadn’t realized that doing so early would help secure teachers and resources.

“We were very well received,” said Izabela Miller, principal of Amidon-Bowen Elementary in Southwest, which was at 40 percent of its target enrollment before the first round of door-knocking in late June. Now the school is at 70 percent, and Miller and her volunteers are headed out for another round of canvassing this weekend.

Many principals said they planned to canvass more broadly in an effort to find and recruit new students. “I can still go up and down the street, maybe find someone looking to go to a charter school and persuade them to go to Garfield,” Branch said.

Branch has already come up with his own strategies for retaining students, and he has beat his enrollment targets every year. Starting in April, he offers a treat — a ice pop party or a movie — every Friday for students who have re-enrolled. In June, he puts on a day-long carnival, and only those students who have completed their enrollment paperwork are admitted to the choicest parts, such as the waterslide, the Ferris wheel and the dunk tank.

Most Garfield parents had re-enrolled before this year’s carnival day, and many others showed up that morning bearing last-minute paperwork. One of them was Danielle Wise, the mother of an 8-year-old.

“He said don’t forget to come to my school! Don’t forget to register me!” said Wise, who recently moved outside Garfield’s attendance zone but wouldn’t consider transferring her son.

Caruthers, the West Education Campus principal, and her team of volunteers — two parents, a kindergarten teacher, a counselor and a central-office employee — made their inaugural canvassing trip on a recent Saturday morning. Each was armed with a “walk list” of student names and home addresses, and they had smartphones with mapping apps, school fact sheets and door hangers to leave at houses where no one answered the door.

Students no longer lived at the first three addresses that Caruthers tried. But the next three doors yielded face-to-face conversations with parents and grandparents and — the next week — three sets of filled-out enrollment forms.

“We’re doing a lot of great things at West, and people should know that,” Caruthers said. “We need to make sure that we keep our kids.”