A top advisor to former Chancellor Joel Klein who resigned shortly after Cathie Black took office is embarking on a new career as a professor to principals.

Former Deputy Chancellor Eric Nadelstern, who hinted last month that he’d been offered a teaching position, is taking a job at Columbia’s Teacher College as a professor of practice in educational leadership. Nadelstern told me today that he also has plans to author two books — one about the lessons he’s learned in urban education reform and one about his time as a principal and deputy chancellor.

Nadelstern, who left the Department of Education last month, was the most senior educator among Klein’s top advisors. He began teaching in 1972 at Dewitt Clinton High School, the high school from which he graduated, and has since worked at almost every level of the city’s education system.

He was also the subject of much speculation when Klein stepped down last year, as many thought Nadelstern would be named chancellor. But when Mayor Bloomberg appointed Black and and Deputy Chancellor Shael Polakow-Suransky was named her second in command, Nadelstern’s departure seemed inevitable to many observers.

At Teachers College, where Nadelstern got his Master’s Degree in 1973, he will mainly teach people who are studying to become principals and superintendents, as well as some who already are. Asked what lessons he planned to impart from his time in New York City’s school system, Nadelstern said he would preach a doctrine of independence.

“Ultimately the principals I respect most are the principals who have historically practiced creative noncompliance,” he said.

“Essentially, the strategy I used during my 17 years as a principal was regardless of departmental policy, I would do what was in the best interest of my school and my students. Sometimes that coincides and sometimes it doesn’t.”

The irony, he’ll admit, is that for much of the last decade, it’s been part of his job to get principals to conform to what he and other administrators’ believed was best.

Looking beyond the next three years, Nadelstern said was concerned that the city would reverse some of the changes he helped engineer.

“I expect at some point in the next administration there will be an effort to return to the imagined perfection of the past and I would encourage principals to fight for their hard-earned and absolutely necessary autonomy and empowerment if schools are going to continue to serve our students well,” he said.

Nadelstern is also serving as a member of the transition team for New Jersey’s new Education Commissioner Christopher Cerf, with whom he worked under Klein, and will be a senior fellow at the Woodrow Wilson National Fellowship Foundation.