CHICAGO (CBS) — Chicago Teachers Union president Karen Lewis is apologizing for a mocking remark she made about U.S. Secretary of Education Arne Duncan.

As WBBM Newsradio’s Bernie Tafoya reports, Lewis says her remarks were just an attempt to lighten the mood when she took a shot at Duncan at a conference with teachers union leaders in Seattle last month.

The video of Lewis’ speech was posted on YouTube by the Education Action Group, which has given it the title, “CTU President Karen Lewis Uncensored – NSFW,” although it does not have any obscene language or subjects that would appear to deem it “not safe for work.”

As of Tuesday morning, the clip had 2,764 views.

LISTEN: WBBM Newsradio’s Bernie Tafoya reports

Lewis is shown pacing back and forth in the four-minute clip, which was taken from a speech that lasted more than half an hour.

“This guy has the nerve to stand up say, ‘Education is the civil rights issue of our time,’” Lewis said, adopting a low, lisping monotone voice to mock Duncan as she quoted him. “But you know he went to private school, because if he had gone to public school, he’d have had that lisp fixed.”

Lewis also called Duncan unqualified, noting that he only holds a Bachelor’s degree in sociology from Harvard, where Lewis claimed “it’s hard to get in, but it’s not hard to stay.” She suggested that Duncan probably had not taken any math or science classes at Harvard, since they are not required.

“If the president had appointed the custodian who works in a hospital Surgeon General, what would the physicians have done?” she said. “I think they’d be beyond that. They’d have risen up and said, ‘Have you lost your mind?’ ”

She went on to say, “He was an athlete, so he might not have been self-medicating, but I wouldn’t count on it.”

Duncan was the co-captain of the varsity basketball team at Harvard, and later played professional basketball in Australia.

Lewis went on to address other subjects in her speech, including a Chicago Tribune editorial cartoon, which she characterized as “a vicious, nasty cartoon of me, with my fat butt sitting on a little tiny chair in the corner with a dunce cap on.”

Later, she remarked that while attending Dartmouth College, she “spent those years smoking lots of weed; self-medicating.”

The union said Lewis spoke with Duncan on Monday afternoon about her remarks.

“Karen Lewis has always been candid and outspoken when discussing the personalities and policies that have adversely impacted public education in our nation,” union spokeswoman Stephanie Gadlin said in a statement. “The observations she made about herself and other public figures were an attempt at humor and candor before a live audience.”

The video was picked up by conservative Web publisher Andrew Breitbart’s “Big Government” site, which characterized the clip as “laced with potty talk” and “cheap personal attacks” on Duncan.

In its statement the Teachers Union complained that the video was being used as a tool by “right-wing, anti-public education advocates.”

“Though these comments were made more than a month ago, today they are being presented out of context in order to shift the focus from bad public policy decisions in education to attacks on her character,” said Gadlin said in the statement.

The Education Action Group, which originally posted the video on YouTube, does say on its own Web site that it does not support teachers’ unions.

“Breaking the power of Big Labor in America’s schools would allow parents, administrators and teachers to be free to make decisions in the best interest of students,” the Web site says. “Onerous labor contracts and work rules, designed to defend adults’ rights, hinder innovation and improvement.”

Duncan led the Chicago Public Schools system before he was appointed Education Secretary following the election of President Obama. In both Chicago and Washington, Duncan has clashed with teachers’ unions over the expansion of non-union charter schools and other issues.

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