As many states and districts rethink teacher supervision and evaluation, the team at the Measures of Effective Teaching (MET) Project, funded by the Bill and Melinda Gates Foundation, has analyzed thousands of lesson videotapes and studied the shortcomings of current practices. The tentative conclusion: Teachers should be evaluated on three…

Teacher evaluation is problematic because it combines two conflicting tasks: improving instruction and judging performance. A Boston elementary principal gradually devised an informal supervision/evaluation system involving brief, random, and frequent classroom visits followed by praise, affirmation, suggestions, and constructive criticism. Even…

A principal boasts that he spends two hours a day in classrooms. And it is true--he really does visit his school's 17 teachers daily, chatting with students and occasionally chiming in on a lesson. But when teachers are asked what kind of feedback they get, they say the principal rarely talks to them about what he sees when he strolls through…