Pittsburgh was once one of Bill Gates’ favorite cities. He showered it with millions to try out his ideas about how to improve teaching and test scores. But it didn’t work.

Now Superintendent Anthony Hamlet is scrapping the last vestiges of the Gates plan.

Pittsburgh Public Schools is scrapping a performance-based pay system, giving all its teachers at least a 2 percent raise and paying its least experienced teachers as much as 15 percent more per year.

The tentative changes are included in three-year contracts overwhelmingly approved Wednesday by the Pittsburgh Federation of Teachers, said Nina Esposito-Visgitis, the union’s president. The union represents about 3,000 teachers and support staff.

A little more than 2,000 members voted on the contracts, which were approved by 90 percent of teachers, 90 percent of paraprofessionals and 77 percent of technical and clerical employees.

“We really focused on the new teachers. We were falling behind other districts in terms of our starting salary,” Esposito-Visgitis said. “A lot of money was put at the bottom of the salary schedule because we want to attract the best and the brightest in Pittsburgh.”

Superintendent Anthony Hamlet issued a statement Wednesday night thanking “parents, stakeholders and the larger city for their patience” through stalled negotiations that nearly culminated in districtwide school closures.

Hamlet said he expects the new contracts to help reduce teacher turnover and improve school stability.

“It’s a testament to our members and to both negotiating teams that we were able to resolve things,” Esposito-Visgitis said. “We’re glad this chapter is over.”