After nearly a year of negotiations, the city and the Boston Teachers Union reached a tentative contract agreement that would give educators a pay raise, family leave benefits and reductions in some class sizes.

All staff will receive 2.5-percent raises for three years with additional pay increases for some employees. The first year of the contract would also be retroactive.

The tentative contract was announced at the American Federation of Teachers conference in Boston on Thursday morning by Mayor Michelle Wu and BTU president Jessica Tang, who is also a vice president in the AFT.

"After working over 11 months without a contract, just yesterday, we were able to reach a tentative agreement that will help us to create the schools our students and educators deserve," Tang told the crowd at the Boston Convention and Exhibition Center. "Despite the challenges, so many of us are facing, we know that when we fight when we fight, when we fight."

Tang referenced the city's protracted fight with state education officials, who recently threatened to take over the district under a legal process known as receivership. She credited Wu for reaching an agreement with the state that would give the district time to correct the problems it has faced in ensuring special education students and other vulnerable populations receive necessary services.

Wu appeared energized at the conference.

"I am so excited about the ways in which this new agreement with the Boston Teachers Union clears the way for our school system to take meaningful steps to support our educators and help transform the experience for students across all of our communities," she said. "I just want to say thank you again to everyone who was part of making this agreement possible, and for demonstrating that when we're given the time and opportunity to listen to the needs of all of our stakeholders, our students and educators, our families, we can deliver the change that our communities deserve now."

The city did not disclose the full terms of the contract, saying it had yet to be ratified or voted on by union membership. That is planned for September.

Wu specifically noted that the contract would benefit students with disabilities and multilingual learners and extend a pilot program that would identify housing for BPS families without a home. Wu also said the contract maintains "as a baseline" the ratio of support staff, like guidance counselors, school psychologists and social workers.

According to a union letter to members, the contract honors a commitment to overhauling special education, including targeted reductions in class size and the hiring of more educators depending on student needs.

The city's paid family leave policy will now also apply to teachers' union members, giving them 12 weeks of paid leave. Additionally, the contract will recognize Juneteenth as an official holiday, and staff who want to celebrate Three Kings Day, Lunar New Year and Diwali may take them off without needing to use personal time.