Thousands of Teach for America alumni flooded the Walter E. Washington Convention Center on Saturday to celebrate the 25th anniversary of the organization, which is known for placing striving, idealistic and inexperienced teachers in some of the nation’s neediest schools.

The D.C. conference featured hundreds of speakers, including some of the most prominent names in education reform such as acting U.S. education secretary John King, former New York City schools chief Joel Klein, D.C. Schools Chancellor Kaya Henderson and her predecessor Michelle Rhee.

Also on the agenda was a panel of speakers including Randi Weingarten, president of the American Federation of Teachers and a frequent TFA critic. The TFA — lauded for attracting high-achieving college graduates, and criticized for underplaying the importance of poverty in schools and placing novice teachers with the neediest children for only two-year stints — has been trying to shed its reputation as a polarizing force in education.

“We have people who are not Kool-Aid drinkers, which is great, and people who are Kool-Aid drinkers, which is great,” TFA chief executive Elisa Villanueva Beard said of the conference.

She said the summit comes at an inflection point for the organization and for education reform at large. Although there has been progress toward equity in public schools, she said, there hasn’t been enough, and TFA is trying to be “very clear-eyed about what it’s going to take to move the needle.”

Wendy Kopp founded Teach for America 25 years ago. (Stephen Lovekin/Getty Images)

In a sign of TFA’s political firepower, President Obama recorded a congratulatory video message to be played at a Saturday night gala. He listed the many ways in which TFA’s 50,000 alumni exercise influence, from continuing in the classroom as teachers to starting their own schools to running for political office.

“There are even TFA alumni working for me in the White House,” Obama said.

Saturday’s sessions dealt with a wide range of issues, including how to better serve Latino students, the need for more diverse educators, the role of white leaders in education reform, and rural education. Two leaders of the national Black Lives Matter movement — Brittany Packnett, executive director of TFA’s St. Louis office, and DeRay Mckesson, who last week filed papers to run for mayor of Baltimore — spoke about connections between education and civil rights.

And in one popular session, hundreds of alumni listened to speakers discuss how to dismantle the school-to-prison pipeline, a discussion that began with a challenge and a criticism from one of TFA’s own.

“Here is the inconvenient truth: Education, including education reform, is part of the problem,” said Cami Anderson, the polarizing former schools chief in Newark, N.J., and a 1993 TFA alumna. “We have not made a dent in the problem, and in some cases we’ve made it worse.”

Anderson said that the reform movement of which TFA is a part has for too long turned a blind eye to complaints about schools “quietly pushing out the most difficult kids,” meting out excessively harsh discipline and having high rates of suspension and expulsion.

“Why has the school reform community been largely silent about the school-to-prison pipeline?” she said.

Erin Stauber, who served with TFA a decade ago in the Mississippi Delta, said afterward that she appreciated the challenge. Stauber is still in the classroom, teaching third-graders at a D.C. school, and said she came for the chance to reconnect with TFA’s network and its message about the need for educational opportunity.

King, the acting education secretary, also addressed the school-to-prison pipeline, calling it a civil rights issue that can be solved only with more equitable schools, a more diverse teaching force and criminal justice reform.

He spoke of the importance of second chances in his life: After he was orphaned at age 12, King made it to Phillips Academy Andover, the prestigious New England prep school, only to be expelled.

“I acted out. I made bad choices. I got kicked out of school, and folks could have given up on me as we give up on so many young people,” he said. Instead, he said, adults in his life did not give up on him, and he went on to earn three Ivy League degrees.

King also co-founded Roxbury Prep, one of a new class of “no excuses” charter schools in Massachusetts that serves mostly minority students, has strict discipline codes and a high rate of suspensions. He did not talk about Roxbury Prep on Saturday.