PORTLAND — School Superintendent Jim Morse announced today that he will retire when his three-year contract runs out at the end of June.

Morse, 57, took the job as head of the city’s public schools in July 2009, on the heels of a financial crisis that resulted in the firing of a superintendent and a business manager.

Morse said he had no idea how “broken” the school district was when he became superintendent, but he has done the “hard work of transformation” that will allow the district to excel when he “passes the baton” to his replacement.

“I’ve made the changes necessary to make this a high-performing district,” Morse said. “There’s still a lot of work to do, but now you have the infrastructure to build success.”

Morse informed the School Board on Tuesday during an executive session that he would not seek a contract extension. Morse’s contract wasn’t extended last year, either. His annual salary is $131,500.

Morse’s efforts have been praised by some and criticized by others. Under his leadership, the district adopted a five-year budget planning process, reorganized central office administration, began developing a systemwide curriculum and is about to adopt a comprehensive plan.

“Jim has been a change agent,” said Kate Snyder, board chairman. “The dysfunction went deeper than any of us realized. The changes he’s made haven’t been easy, but they’ve been critical. Is it happening fast enough for everyone? Of course not. It never does.”

Before coming to Portland, Morse was superintendent of the Messalonskee School District in Oakland, near Waterville, and superintendent of the Maine School of Science and Mathematics in Limestone.

A Portland native, Morse has homes in Portland and Unity.

Morse said he has no concrete plans following his retirement, but he’s cultivating job offers that he has continued to receive since taking the Portland post.