What’s the first thing Michelle Rhee would do if she returned to her former post as chancellor of D.C. schools? She’d convene a meeting of all the school system’s teachers, to do something she says she did badly during her first stint: communicate.

“It was one of my biggest mistakes,” Rhee said Thursday at the Sixth and I Historic Synagogue in Northwest Washington. “I wasn’t doing a good enough job communicating directly and consistently with teachers about what I was doing and why.”

In town to promote her new memoir, “Radical: Fighting to Put Students First,” Rhee reviewed her tumultuous D.C. tenure in an hour of onstage conversation with Richard Whitmire, who wrote a biography of the former chancellor.

She stood by the sweeping changes she brought to the troubled school system, including the abrupt closure of 23 schools in 2008 and the introduction of evaluations that for the first time linked teachers’ pay and job security to their students’ test scores.

The problem wasn’t the policies, Rhee said, it was how she and her political patron, then-Mayor Adrian M. Fenty (D), sold those policies — or failed to sell them.

Rhee left office in 2010 after Fenty lost his reelection bid to current Mayor Vincent C. Gray (D) — in part, the thinking goes, because Rhee’s style of reform had alienated voters and teachers’ unions.

“What I know now is how you do something is just as important as what you do,” she said. “On that . . . we fell short.”

After leaving Washington, Rhee founded Students First, a grass-roots advocacy group that lobbies on education issues in statehouses around the country.

Speaking before a friendly audience — many of whom were current or former teachers, according to a show of hands, and many of whom clutched copies of “Radical” — Rhee said the second thing she’d do now as chancellor is seek the power to authorize charter schools.

When Whitmire, her biographer, asked whether the school system can compete with charters — audited enrollment figures released last week show that 43 percent of the city’s students are now in charter schools, up from 41 percent last year — Rhee called the question “weird.”

The conversation shouldn’t be about who’s winning the competition between charter schools versus traditional schools, she said. It should be about whether students are enrolling in effective or ineffective schools.

“I didn’t see it as competing,” she said of her stance on D.C. charter schools. “I was focused on making sure that all kids were in a high-performing school.”

That may come as news to charter school advocates in the District, many of whom didn’t see Chancellor Rhee as an ally. In any case, Rhee’s successor, Kaya Henderson, is now seeking the chartering authority that Rhee wishes she’d had.

“I think the city is in­cred­ibly lucky to have Kaya at the helm,” Rhee said. “She is an extraordinary leader.”