The classrooms are being studied in Charlotte-Mecklenburg Schools, the Dallas Independent School District, Denver Public Schools, Hillsborough County Public Schools in Tampa and St. Petersburg, Fla., Memphis City Schools, The New York City Department of Education and Pittsburgh Public Schools.

The main conclusions of this report are as follows:

— High quality classroom observations require clear, specific standards, well trained and certified evaluators and multiple observations per teacher.

— Classroom evaluation is not enough. That information should be combined with student feedback and data on improvement in student test scores. Combining the three kinds of evaluations offsets the weaknesses of each individual approach.

— The different evaluation methods still need to be refined, but they’re better than what most districts are using now.

Memphis Public Schools used to evaluate its teachers once every five years. With financial help from the Gates Foundation, the district has switched to a system of four-to-six classroom visits by both principal and peer evaluators, followed by feedback meetings focused on improvement.

The new system was implemented after teachers and administrators worked together to set new district-wide standards and both teachers and principals were thoroughly trained in the new system.

“This process is neither quick nor easy. And we’re still working out the kinks,” said Tequilla Banks, coordinator of research, evaluation and assessment for the Memphis district.

She said, however, that both teachers and administrators feel the effort is worth it.