Mitchell Trockman has been a teacher, a principal and an interim superintendent three times with the Minneapolis School District.

After 53 years and a previously failed retirement, he says he is leaving the district for good.

Trockman, who most recently served as the board liaison, says the challenges in the district were never ending. That kept him coming back. He has served in at least 15 different positions.

“Leaving at a high point in one’s career is better than waiting to be asked to leave,” Trockman said.

Trockman, 75, says he grew up in an immigrant family that placed immense value in education. Although he is serious about his retirement from Minneapolis, he is not ready to quit working in education.

He says he admires the University of Minnesota’s College of Education and Human Development and is searching for an opportunity to work there.

“Supporting that effort seems to make sense to me,” he said.

The Minneapolis school board and interim superintendent recently celebrated Trockman’s accomplishments at a school board meeting, saying he played a vital role in keeping the board organized.

Jenny Arneson, the board’s chairwoman, said Trockman is the “guy who knows everything about Minneapolis Public Schools.”

With such a long tenure at the district, Trockman will take with him decades of institutional knowledge. Tracine Asberry, another board member, said she has heard Trockman recall almost every major decision made by the district’s superintendents and the impact.

As board liaison, Trockman’s job was to be the intermediary between the board and district staff.

He helped get documents when board members had questions. He helped schedule meetings and other important tasks. Interim Superintendent Michael Goar said Trockman’s role is a “thankless job.”

“We get crabby and often ask, ‘Why are you asking for that?’ ” Goar said of the executive staff. “[Trockman] serves his role with a degree of humbleness and commitment.”