"All too often, during the eight years of the Bush administration we heard teachers and the unions that represent them be demonized," said Randi Weingarten, president of the American Federation of Teachers, which represents more than 1.4 million educators, mostly in urban areas.
"I think he cares deeply about stopping this people-in-different-camps mentality and the blame game and the scapegoating," she said.
Teach for America founder Wendy Kopp said, "He expects people to come together across philosophical and political lines and work in the interest of kids."
That Duncan isn't a politician may be another challenge.
A Harvard graduate, Duncan left school for a year to tutor disadvantaged children in Chicago's South Side in a program his mother founded to help African-American children 48 years ago.
"It's in my blood," Duncan said. "We worked in a neighborhood where the families were very, very poor and pretty broken, frankly."
Duncan said he believes that children from any background can achieve with the right support.
"When we give our children real opportunities, real support, real guidance, have the highest of expectations, they can do unbelievable things," he said. "That's what drives me everyday, is knowing how much potential children have if we as adults meet them half way."
Duncan was the co-captain of Harvard's basketball team and played professional basketball in Australia for four years, where he met his wife, Karen. They have two children, Claire, 7 and Ryan, 5, who attend school in Arlington, Va.
Before Obama nominated him to his cabinet, Duncan spent seven years running the Chicago schools system, where his unconventional methods attracted controversy.
In 2004, he made potential dropouts sign a form acknowledging, "I will be more likely to rely on the state welfare system for my livelihood."
Last year he launched a program in 20 Chicago schools to pay students for grades, funded by private donations.
He raised the ire of the teachers union by closing failing Chicago schools and, he said, "moving all of the adults out."
"It's arbitrary," Stocks of the National Education Association said. "It assumes that all of the adults in the school building are not serving the needs of children, but there are better ways of turning around a school."
Added Weingarten: "What we're saying is work with teachers, not do things to them."
Duncan has already faced controversy for his desire to see more charter schools across the country and the Obama administration's opposition to school vouchers.
"When you broad-brush charter schools as being innovative and the way for reform, you discount all of the innovative efforts that are going on in the public school systems." Stocks said.
Chavous of DC Children First complained that the Obama administration caved under union pressure to scrap a voucher program in Washington that allowed thousands of children to attend a different school, a program that he said was working.
"This administration's response to this voucher issue in D.C. speaks volumes about their overall commitment to reform," Chavous said. "The only reason to be against this program is politics."
But the unions argued the voucher program in D.C. didn't live up to promised student achievements.