Maryland education officials, teachers unions and other education organizations signed a written agreement Friday to collaborate on methods for assessing classroom effectiveness, a central element of the state’s evaluation system for teachers and principals.

Leaders representing teachers, principals, superintendents and other policymakers gathered in Baltimore to formalize the 12-point document, which they said will strengthen the evaluation system. The signing came during a meeting of the Maryland State Board of Education, one of the parties to the agreement.

Teacher and principal evaluations have been controversial across the country, and Maryland’s unusual agreement comes amid continuing tensions over other aspects of educator evaluations.

“This level of statewide collaboration is unprecedented nationally,” said Bill Slotnik, founder of the Community Training and Assistance Center, a nonprofit group that has worked with 30 states on teacher and principal evaluations. In Maryland, he said, “the key constituencies are saying, ‘If we’re going to have effective implementation, we’re better off working together to make that happen.’ ”

The agreement focuses on setting learning objectives for students, carefully planned goals of what a student is expected to learn over a given time period. The objectives, developed between educators and their supervisors, are a key factor in Maryland’s evaluation system.

Under the agreement, those involved will work to develop “rigorous and measurable, but obtainable” objectives.

Charlene Dukes, president of the State Board of Education, said in an interview Friday that the agreement was an important advance that shows a shared commitment to classroom success. She said it would mean “listening to each other, talking to each other and putting forth the best strategies.”

In its bid for $250 million in federal Race to the Top funds, Maryland included a proposal to create a statewide evaluation system.

The issue of using standardized test scores in evaluations has been a flash point — especially as Maryland switches to new Common Core-aligned assessments — but Maryland officials said that data from state standardized tests will not be a factor until 2016-2017, when results from the new Common Core tests will first be used.

The agreement signed Friday addresses professional development programs and establishes a network for collaborating on evaluations. Although the agreement recognizes the importance of local flexibility, it also aims for consistency and a common language across the state. Additionally, it calls for a study, by August 2016, focusing on the implementation of student learning objectives.

“For us, it is an attempt to help our members be able to do this right so that it is a benefit to them and to their students in terms of offering the best opportunities to learn and grow,” said Betty Weller, president of the Maryland State Education Association, the state’s largest teachers union.

Weller said the collaboration emerged from teachers’ efforts to get grants for more professional development. The partnership is helpful, she said. “We’re all trying to do the education-reform stuff, and many times we’re doing this in different directions,” she said.

Jack Smith, chief academic officer of the Maryland State Department of Education, said the effort will draw on best practices and emerging research and involve a wide range of educators and policy­makers. “The coming together and the collective IQ are really important,” he said.

Tom Israel, executive director of the Montgomery County Education Association, called Friday’s agreement worthwhile but said the issue has not been particularly controversial, because Montgomery began implementing student learning objectives last school year.

Far more divisive, he said, is the issue of standardized test scores as a fixed percentage in teacher evaluations statewide. In Montgomery, he said, teachers have to “examine, discuss, present and explain” a wide range of student data, but “there is not a simplistic mathematical formula.”

Lyndsey Layton contributed to this report.