AT ONE point during Monday’s rowdy forum on D.C. education, a mayoral candidate wondered why the city even needed a schools chancellor. It was a silly assertion, made by a long-shot candidate. But the fact that it drew cheers spoke volumes about the mind-set of the crowd and the group that organized the event. Neither is a credible gauge of the success of public education reform in the District.

Boos and catcalls seemed to be the order of the night, The Post’s Emma Brown and Aaron C. Davis reported. Mayor Vincent C. Gray (D), making his first appearance at a campaign debate since announcing his plans for reelection, came in for a particularly hard time at the event, which was sponsored by the Washington Teachers’ Union, as did D.C. Council member Jack Evans (D-Ward 2). Good for them for standing up for the sensible policies that have brought much-needed change to the city’s public schools. Shame on those who pandered to the noise.

By any measure — enrollment, test scores, graduation rates — progress has been made both by both the city’s traditional school system and public charter schools. Much work still must be done, but it was unimaginable in 2007, when then-Mayor Adrian M. Fenty engineered the mayoral takeover of what was one of the nation’s worst school systems, that D.C. schools could show the most overall gain in the country on the 2013 National Assessment of Education Progress. “A remarkable story,” said Education Secretary Arne Duncan of the D.C. record.

At the heart of the turnaround are reforms grounded in accountability, high standards and school choice. D.C. teachers are now rigorously evaluated; those who are most effective are rightly rewarded with more money while those with consistently poor records of not helping students achieve are dismissed. The teachers union has resisted some of the policies that have led to real results for students; indeed, it backed Mr. Gray in 2010 in the hope that he would reverse the controversial reforms started by Mr. Fenty and former schools chancellor Michelle A. Rhee. Instead, Mr. Gray wisely chose Kaya Henderson, Ms. Rhee’s deputy, and has given her critical support.

Fewer than 1,000 teachers — 839 out of a workforce of about 4,000 — participated in the union’s election in July, and Elizabeth Davis was named president with just 459 votes. In the complex debate on school reform, she’s entitled to be heard. So are the many teachers who want to be rewarded for the quality of their work, and the thousands of children and parents who are grateful for the improvements in D.C. schools.