WASHINGTON — Leaked documents from a prominent conservative think tank show how it sought to teach schoolchildren skepticism about global warming and planned other behind-the-scenes tactics using millions of dollars in donations from big corporate names.

More than $14 million of the money used by the Chicago-based Heartland Institute would come from one anonymous man, according to the documents prepared for a meeting of the group’s board.

Heartland is one of the loudest voices denying human-caused global warming, hosting the largest international scientific conference of skeptics on climate change. Several of its documents were leaked this week to the news media, showing the planning and money behind its efforts. Heartland said some of the documents weren’t accurate, but declined to be specific.

As detailed in the papers, Heartland’s plans for this year included paying an Energy Department consultant $100,000 to design a curriculum to teach schoolchildren that mainstream global warming science is in dispute, even though it’s accepted by the federal government and nearly every scientific professional organization. It also pays prominent global warming skeptics more than $300,000 a year and plans to raise $88,000 to help a former TV weatherman set up a temperature records website.

“The stolen documents appear to have been written by Heartland’s president for a board meeting that took place on Jan. 17,” Heartland said in a statement. “The authenticity of those documents has not been confirmed.” The institute singled out one of the six documents — claiming to be a summary of efforts on the issue of global warming — as a fake.

Because Heartland was not specific about what was fake and what was real, The Associated Press attempted to verify independently key parts of separate budget and fundraising documents that were leaked. The federal consultant working on the classroom curriculum, the former TV weatherman, a Chicago elected official who campaigns against hidden local debt and two corporate donors all confirmed to the AP that the sections in the document that pertained to them were accurate. No one the AP contacted said the budget or fundraising documents mentioning them were incorrect.

David Wojick, a Virginia-based federal database contractor, said in an email that the document was accurate about his project to put curriculum materials in schools that promote climate skepticism.

“My goal is to help them teach one of the greatest scientific debates in history,” Wojick said. “This means teaching both sides of the science, more science, not less.”

Five government and university climate scientists contacted said they were most disturbed by Wojick’s project, fearing the teaching would be more propaganda rooted in politics than peer-reviewed science.

Businesses and other interests often offer free curriculum materials to financially strapped schools, hoping that teachers will use them and help disseminate their views or promote their products.

Energy Department spokeswoman Jen Stutsman said Wojick’s federal work has nothing to do with climate change and that the agency maintains that global warming is real and man-made.

Heartland also planned to spend $210,000 to help Cook County Treasurer Maria Pappas tour the nation to speak about municipal debt, according to one document. Pappas lost to Barack Obama in the 2004 Democratic primary for a U.S. Senate seat. Pappas confirmed this in a phone interview, saying what Heartland was doing was exposing a “financial tsunami” of municipal debt.

The documents also show Heartland has raised more than $2 million from large insurance companies and nearly half a million dollars from tobacco interests.

A person who emailed 15 media and bloggers as “Heartland insider” sent six different documents purporting to be from the libertarian think tank. The insider then killed the email account used to send the documents and could not be reached. Heartland spokesman Jim Lakely would not confirm or deny the claims made in the five documents that he did not call fake.

The most sensational parts of the documents — and much of what has been confirmed independently — had to do with global warming and efforts to spread doubt into what mainstream scientists are saying. Experts long have thought Heartland and other groups were working to muddy the waters about global warming, said Harry Lambright, a Syracuse University public policy professor who specializes in environment, science and technology issues.

“Scientifically there is no controversy. Politically, there is a controversy because there are political interest groups making it a controversy,” Lambright said. “It’s not about science. It’s about politics. To some extent they are winning the battle.”

A 2010 study in the Proceedings of the National Academy of Sciences surveyed more than 1,300 most cited and published climate scientists and found that 97 percent of them said climate change was a human-made problem. Yet, public opinion polls show far more doubt in the American public.