The St. Paul school district and the teachers' union have reached a tentative contract agreement, Superintendent Valeria Silva said Friday morning.

"We have a tentative contract agreement!" she tweeted shortly after 9:30 a.m. "Time now to rest, clear our sidewalks (again), and get back into the classrooms on Monday!"

The two sides bargained late into the night Thursday before reaching the deal.

They are expected to release a joint statement later today.

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Negotiators for the St. Paul public schools and the union representing its teachers took extra time Thursday in talks aimed at averting a strike.

The 12-hour-plus mediation session came just four days before teachers were set to vote Monday on whether to give union leaders permission to order a walkout.

The two sides met privately, a stark contrast to the public events of recent weeks. Heading into the session, leaders on both sides had expressed optimism, but it was not known late Thursday what type of progress was being made as the talks continued.

Earlier, the St. Paul Federation of Teachers said that it expected to release a short written statement about the talks Thursday night, but there was no word when this edition went to press.

Union leaders scheduled a "media availability" regarding the contract talks for Friday morning. (Check startribune.com for updates.)

Last week, the federation raised the stakes on this week's negotiations by scheduling the strike authorization vote. But it also held open the possibility of calling off the vote if significant progress was made Thursday on the union's contract goals.

The sides have been divided on union proposals to limit class sizes, increase the number of support-staff members such as nurses, media specialists and counselors, and expand preschool opportunities — priorities that union President Mary Cathryn Ricker said would take the contract into the 21st century.

Still to be resolved, but seemingly less of a concern, was the issue of wages and benefits. The average St. Paul teacher salary is $68,436 — part of a wage-and-benefit package totaling about $92,000. Entering Thursday's talks, the sides were about $9 million apart on their respective compensation proposals.

The union called upon community members to help it create its priority list, and in recent weeks it has tapped into that communal spirit by staging public events.

On Jan. 30, the union enlisted parents and students to attend "walk-in" rallies outside the schools. Then, this week, before the school board's monthly meeting on Tuesday night, community members joined scores of teachers in rallying on behalf of the union and its proposals.

But while several parents spoke of a willingness to walk picket lines with teachers, leaders within the black community — as well as Mayor Chris Coleman — warned that a walkout threatened student learning and the progress being made on issues such as raising graduation rates.

"After years of working to close a stubborn achievement gap, we are finally making real, substantive progress," Coleman wrote in a letter Wednesday to Ricker and Superintendent Valeria Silva urging the two sides to reach an agreement. "Now is not the time to stop."

Anthony Lonetree • 651-925-5036