New York, NY —

Mayor Bloomberg says the city will use student test scores in evaluating teachers coming up for tenure this year, despite a state law that seems to prohibit such a practice. WNYC's Beth Fertig has more.

REPORTER: The mayor says city attorneys believe the law only applies to teachers hired after July of 2008. That means teachers hired in 2007, who are now coming up for tenure, can be evaluated based partly on test scores.

About six thousand teachers would affected. The mayor made the announcement at an event in Washington where he spoke with US Education Secretary Arne Duncan. Duncan supports using student achievement data in part to evaluate teachers.

The city says along with the test scores, principals could also use class room observations to evaluate teachers. The teachers union claims tests are flawed are not a fair measurement of a teacher's effectiveness. Bloomberg's announcement comes as teachers negotiate a new contract with the city. For WNYC I'm Beth Fertig.