Now that the new teachers contract is in place, schools face a high-stakes game of scheduling Tetris.

One option is for schools to squeeze 150 minutes of newly required teacher meetings into two days without exceeding work-time limits, sacrificing any class time, or jeopardizing after-school programs. Another choice is to spread the minutes out over more days.

Either way, schools only have until Friday to figure it out, when schedule changes are due.

“This discussion needs to happen immediately,” United Federation of Teachers President Michael Mulgrew wrote in an email to teacher-leaders just hours after the contract was ratified Tuesday evening.

The scheduling puzzle represents just the first set of time-sensitive choices that schools must make to comply with new rules and take advantage of new opportunities in the contract.

They must also decide by the end of this month whether to submit school-experimentation proposals, even as they are unsure what the new program entails. And school leaders must make budget decisions, even as it is unclear how new pay incentives will be funded.

At the same time, schools must continue to give end-of-the-year exams, plan for summer school, and finish teacher evaluations, which are also due Friday.

“It’s just a tremendous amount of information for us to interpret,” Joanna Cohen, assistant principal of P.S. 2 in Chinatown, said of the contract and everything else piled on schools’ plates. “It’s pretty overwhelming.”

The contract’s most pressing provision is the schedule change: After-school time that had been reserved for tutoring has been converted into time for teachers to train, collaborate, and interact with parents. The contract offers schools a default weekly schedule that incorporates the changes. But if schools want to make any adjustments, they must be submitted by Friday.

Some adjustments might be minor. P.S. 2, for instance, is planning to start the school day 15 minutes earlier to make sure teachers can meet for the required 80 minutes after school Monday and still leave by 4 p.m., as the contract demands.

Others may be more complicated. For example, Peace and Diversity Academy in the Bronx hopes to negotiate a new bell schedule with another school in its building before the changes are due Friday.

The real riddle for many administrators is how to preserve after-school activities for students now that teachers are required to meet Monday and Tuesday afternoons under the default schedule embedded in the contract.

Teachers at Life Sciences Secondary School on the Upper East Side currently run after-school classes to help students make up missing credits, along with clubs and sports, every Monday through Thursday. With Friday afternoons off-limits for most students, the contract has cut the school’s after-school options in half, said principal Genevieve Stanislaus.

“Monday and Tuesday are off the table,” she said, adding, “We still haven’t fully comprehended how we’re going to make all of this happen.”

The contract’s time rules raise other questions too: Will the new schedule for teachers force principals to work longer days than their own contract rules permit? And how will schools make sure all the new professional development time is useful for teachers?

“Before, we had a month to think about the next meeting,” said David Allen, an assistant principal at Bard High School Early College Queens. “Now, we’re thinking week to week.”

Uncertainty surrounds areas of the contract beyond the new schedule, educators said.

For instance, many schools have expressed interest in the program that would give them new flexibility to make radical changes — but they were unsure what those changes might be. Still, union officials have said they want schools to submit proposals by the end of this month.

Meanwhile, next year’s school budgets are due in a few weeks. Even though their budgets are flat next year, some principals wondered if they would have to help pay for a provision in the new contract that lets top teachers earn up to $20,000 extra per year by taking on new duties.

“Anything that you attach money to,” said Ellen Flanagan, principal of South Bronx Preparatory, “I think you should lay out pretty clearly.”

The Department of Education did not answer specific questions about how the contract might impact school budgets and schedules. A spokeswoman said the department would work with schools as they carry out the new contract rules.

Mark Cannizzaro, executive vice president of the city’s school supervisors union, said principals have asked about the many implications of the new teachers contract, which union officials have relayed to the city. But so far answers are in short supply.

“We really haven’t put any meat on the bones in terms of how we’re going to work these things out,” he said.

Meanwhile, the city has plenty of its own contract-related deadlines.

Under a contract provision meant to reduce a backlog of teacher disciplinary cases, city and union officials must quickly select cases that can be resolved through mediation instead of hearings. The mediation is set to begin July 1. The two sides must also form a host of joint committees to choose teachers for the new leadership roles, review the school-experimentation proposals, and find ways to reduce paperwork in schools.

“We plan to work with the UFT to meet the deadlines established in the contract and work with schools to answer ongoing questions,” said Devora Kaye, the education department spokeswoman.