The contract for D.C. Public Schools teachers is set to expire in less than two weeks, and labor leaders and school officials said negotiations about a new agreement are well underway and should conclude smoothly and soon.

In striking contrast with the bitter union-management feud that sparked Chicago teachers’ seven-day strike earlier this month, Chancellor Kaya Henderson and Washington Teachers’ Union President Nathan Saunders said they have reached broad accord in many key areas.

“I think we’re pretty much there,” Saunders said, adding that the parties are drafting language and expect to deliver a final contract to the D.C. Council before the end of the year.

Neither Henderson nor Saunders would talk about specific terms of the contract, citing the confidentiality of negotiations. But both signaled that while there will be some changes, key elements of the current contract — which weakened teachers’ job protections in return for higher salaries and merit pay — will remain largely intact.

“It’s not going to be the watershed that it was the last time,” Henderson said. “But I think you’ll still see some interesting things.”

Saunders said he had sought to win more job security for effective teachers displaced because of budget cuts or school closures, and Henderson said she hoped the new contract would provide more flexibility for certain schools to add instructional time via a longer school day or school year.

Extended class time is a feature of many high-performing charter schools and an idea that Mayor Vincent C. Gray (D) has publicly championed as a way to lift student achievement. The current contract calls for a 7 1/2-hour workday and a school year of no more than 185 instructional days.

“You want a longer school day, as I said to the chancellor, you need to be prepared to pay for it,” Saunders said. “There are ways to get things done, but it just ain’t free.”

The two sides also have raised the possibility of paying highly effective teachers extra to take on larger class sizes. And there has been some discussion about revising the salary schedule, under which teachers get regular raises based on experience and education.

Not on the table is the District’s teacher evaluation system, which was among the first in the nation to link teacher compensation and job security to student performance on standardized tests.

The evaluation system — called IMPACT — has led to hundreds of firings and has been a point of contention since its implementation in 2009. The Chicago teachers strike was in part to resist a similar form of evaluation.

But the Washington evaluations are not subject to collective bargaining because of a 1996 law, initiated by the D.C. Council and passed by Congress, that gives D.C. school officials sole authority over how teachers are judged.

IMPACT was part of the sweeping changes that took hold after the last contract was approved in 2010.

Negotiations for that contract were contentious and lastedmore than two years, requiring the help of a mediator and pitting then-Chancellor Michelle A. Rhee against then-WTU President George Parker. Henderson, a Rhee deputy at the time, served as the school system’s lead negotiator.

The agreement that emerged gutted tenure rights that had been a cornerstone of the union contract for decades and that, school officials argued, made it too difficult to fire ineffective teachers.

It also linked teacher pay to classroom performance and gave the school system more latitude to decide not to rehire teachers displaced by budget cuts. In return, teachers got substantial pay raises.

Saunders, the union’s vice president at the time, was bitterly opposed to that trade-off. He still regards it as a bad deal for teachers, but now recognizes that its fundamental terms are unlikely to change.

“We never had to be where we are in DCPS,” he said. “But this stuff is in place and I’ve got to deal with it.”

Saunders and Henderson have their disagreements but have struck a collegial relationship, appearing at press events together and taking pains to project mutual respect.

“At the end of the day, I think what Nathan realizes, and what I realize, is if we’re going to just fight, nothing’s going to get done,” Henderson said.

Saunders said working with school system officials is the best way to advocate for his members. He said recent revisions to IMPACT — particularly reducing test scores from 50 to 35 percent of the evaluation — were the result of the informal negotiating he was able to do because of that relationship.

“I understand about fights,” Saunders said. “But there are some times you need to go to the mat and some times you don’t need to go to the mat.”