Is there any hope for reasoned dialogue between the angry forces of left and right that divide our country? I am not seeing much evidence of that in Washington. But something has happened in a small but important corner of American education that suggests smart people on both sides can get together.

Three years ago, I wrote about an acidic battle over revisions in the Advanced Placement U.S. History exam and a 54-page framework that identified topics that might be on the exam.

Many conservatives were furious about the framework, egged on by AP study-guide author and teacher Larry Krieger, who said it "inculcates a consistently negative and superficial view of the American experience." The Republican National Committee and the Texas state school board denounced it. Ben Carson, the future secretary of housing and urban development, said most students who finished the course would "be ready to sign up for ISIS."

Many education experts defended the framework. A College Board survey found 98 percent of teachers and professors thought it was politically balanced. Students and teachers in Jefferson County, Colo., protested when school board members denounced it.

The College Board, which owns the AP system, could have shrugged this off. AP is so deeply woven into high school curriculums and college admission standards that critics were unlikely to have much effect.

But Trevor Packer, the College Board senior vice president who has directed AP for 14 years, took the criticism seriously and sought to address conservative concerns.

Thus began a remarkable series of exchanges. Packer and the professors and teachers of the AP U.S. History development committee initiated a public review period and received particularly substantive feedback from three critics:

●Chester E. Finn Jr., a former Reagan administration education official and a longtime president of the Thomas B. Fordham Institute.

●Frederick M. Hess, resident scholar and director of education policy studies at the American Enterprise Institute.

●Jeremy A. Stern, an independent historian and history education consultant.

Finn and Hess are conservatives. Stern considers himself ideologically neutral in his educational work.

In writing for Fordham's website, Finn said he sympathized with AP's effort to provide a balanced U.S. history course for high schools when the survey college courses it had been designed to mimic were being "replaced or distorted by what's now academically fashionable and politically correct in university history departments."

Hess, in a piece for Education Week, said complaints that the framework had removed historic figures such as Benjamin Franklin were inaccurate. Both the old and new frameworks pointed teachers toward recommended textbooks for the big names. But Hess did detect an anti-conservative spin, which he, Finn and Stern helped AP remove. Hess said the framework stumbled, for instance, by saying Presidents Franklin D. Roosevelt and Lyndon B. Johnson were warriors for justice while Ronald Reagan was a man of "bellicose rhetoric."

Stern sent about 25 pages of commentary to AP. "Rather to my surprise," he said, the development committee incorporated many of his suggested revisions. "The historically crucial rise of relatively egalitarian societies and representative political institutions in the colonies — all but ignored in the 2014 version — is now given due weight," Stern said.

Reforms that seem small to us now, he said, were huge then. "The Jacksonian rise of near-universal white male suffrage, an extraordinarily radical concept in its day, (barely mentioned in the 2014 version) is now properly described," he said.

Even backlash leader Krieger embraced the framework after the committee addressed the conservative complaints. AP U.S. History now is "generating excellent lessons that incorporate critical thinking," he said.

Hess said he was impressed with the honesty of Packer telling him that "it's very difficult, given the dominance of liberal perspectives in college and high school history departments, for faculty committees to avoid unintentionally muting, editing or obfuscating the perspectives of the right."

Our nation's leaders might benefit from the example set by the people with varied political views who improved the AP framework. They did their work with no shouting, but good faith and a mutual desire to get at the truth. That can work in other places.