PROVIDENCE — Supt. Donnie Evans announced his resignation tonight, a surprise move that came just one day before the School Board was scheduled to vote on whether to renew his contract.

In a prepared statement, Evans said he intends to remain in the district through the end of his contract, which expires Sept. 19, to ensure a smooth transition and minimal disruption to the district.

“My decision to leave was not made lightly,” he said. “I want you … to know that my experience in Providence has been both rewarding and challenging. I have decided for personal and professional reasons to pursue other opportunities.”

Evans did not elaborate on his decision to leave, but his tenure has been rocked by a series of missteps in recent months — in particular, the Dec. 13 snowstorm that left more than 100 students stranded for hours on school buses throughout the city. But there have been other decisions that drew criticism during his nearly three years in Providence: the closing of the West Broadway Elementary School, which was later relocated; the increase in class size for special-education students and the furor over the fate of the Nathan Bishop Middle School.

Evans has also faced an increasingly contentious relationship with the Providence Teachers Union, which voted last week to express its lack of confidence in the superintendent and which has begun picketing School Board meetings.

lborg@projo.com