Long a champion of city schools but held back by competing demands as mayor, R.T. Rybak said Wednesday that he'll become executive director of Generation Next, a year-old collaborative that aims to close the achievement gap between white and minority students.

At a news conference, Rybak called the gap "the greatest crisis in our community" and said residents and community leaders will need to respond to it in the same way they did to the I-35W bridge collapse.

"People raced into the water and risked their lives to save other people's lives," he said. "If we can do that with a piece of infrastructure, we can do that with a generation that has tremendous challenges and tremendous potential."

Rybak, who is winding up his 12th year as mayor and is also vice chairman of the Democratic National Committee, leaves City Hall in January after 12 years in office. His successor will be decided in an election on Tuesday.

University of Minnesota President Eric Kaler, co-chair of the Generation Next board, described Rybak as "the "vigorous, visible and dogged campaigner" needed to direct the collaborative.

Rybak also announced Wednesday that he will be teaching a weekly class at the U called "Mayor 101," under a joint appointment with the Hubert H. Humphrey School of Public Affairs and the College of Design. The class, for graduate and undergraduate students, will deal with politics as well as urban design and administration.

His salary at Generation Next has not been determined.

Rybak, who has been on the board of Generation Next since its founding last year, has voiced regret that he was not more deeply involved in education issues until later in his tenure, but said he was pleased that the leading candidates to succeed him have all given it a high priority in their campaigns. In Minneapolis, the mayor has no power over the school system or its board.

Generation Next was announced in late 2012 as a broad-based partnership to focus the spending of millions of dollars already aimed at the achievement gap by backing the most effective among hundreds of programs dedicated to the issue. It involves education, community, government and business leaders trying to improve school performance for children from early ­childhood through early career years.

The group initially found more than 500 initiatives aimed at the gap from birth to college operating in a dozen metro school districts, but Rybak said there was little coherence in those efforts. It has already awarded $800,000 of a two-year, $2 million federal grant to six agencies, and could potentially have $5 million to grant over five years.

Michael Goar, a former school administrator in Minneapolis, Memphis and Boston, was hired as the first executive director, but left after seven months to become the chief executive for Minneapolis schools. Rybak succeeds him. Rybak's long tenure has afforded him more time to get involved in school issues than perhaps any recent mayor.

"I think R.T. has done a pretty good job," said former school board member Judy Farmer. "He's been in schools a lot and he's great with kids. He gets down and talks to them."

Rybak has spoken to each incoming class at the city's seven big high schools to tell them that if they work hard and plan for college and a career, they'll get help in entering and succeeding in college.

The group's efforts are focused on schools in Minneapolis and St. Paul with an aim to reach into the suburbs.

"There isn't a lack of compassion in this community," he told the Star Tribune editorial board Wednesday morning. "There is a lack of alignment."

Minneapolis school Superintendent Bernadeia Johnson said Rybak's appointment is "great news."

"Our mayor has demonstrated consistent passion for improving public education and enthusiastic support for MPS throughout his tenure," she said in a statement. "He has always been available to advise, support and, at times, challenge conventional and status quo thinking. I believe Mayor Rybak is a perfect fit to lead Generation Next."

Asked whether he might run for office again, particularly governor, Rybak said he did not want to "trivialize" his Generation Next work with political machinations. He said Gov. Mark Dayton is likely to run again and he supports Dayton. "It's not even on my radar," he said of another political office.

His predecessor, Sharon Sayles Belton, went on to become a senior fellow at the U's Humphrey Institute before becoming vice president of community relations and government affairs for Thomson Reuters in 2010. Former Minneapolis Mayor Al Hofstede is a registered lobbyist whose clients include those with business before City Hall. Another longtime mayor, Don Fraser, formed the Committee on the Achievement Gap to bring experts together to discuss how to improve minority ­students' academic performance.

Staff writers Steve Brandt and Eric Roper contributed to this report.