New Haven’s educational system finished the year with a strong showing: 90 percent of teachers scored within the top three categories — “exemplary,” “strong” or “effective” — a sign that city representatives say indicates the success of the city’s new teacher evaluation system.

The new method of evaluation takes a top-to-bottom approach and focuses on the development process. This year, 20 teachers who were initially flagged as at risk for dismissal improved their ratings, and 13 percent of teachers were ranked “exemplary” — compared to 8 percent last year.

“The job of turning around schools and raising academic achievement is a complex one and our teachers and administrators have met that challenge with passion,” said Superintendent of Schools Reginald Mayo in a Tuesday statement. “These evaluation results underscore the commitment by both teachers and administrators to demanding nothing short of the best for our kids.”

Twenty-eight teachers, who collectively represented 1.9 percent of the teaching workforce, left the district voluntarily because they failed to improve after receiving a poor rating.

Teachers rated “exemplary” are recognized in their school districts, while those with unfavorable ratings are given training and support. In the past year, five of the 58 teachers who went through training jumped from a “needs improvement” rating to “effective,” while 15 went from “improved” to “developing.”

Fifty percent of teachers said they were satisfied with the system, and 76 percent of principals and assistant principals said they felt the system helped improve classroom instruction, according to the statement.