From Stephanie Simon at  Politico:

The board of the New York state teachers union this weekend unanimously withdrew its support for the Common Core standards as they have been implemented — a major blow for Common Core advocates who have been touting support from teachers as proof that the standards will succeed in classrooms nationwide. 

“We’ll have to be the first to say it’s failed,” said Richard Iannuzzi, president of New York State United Teachers. 

Amid fierce and growing opposition to the standards — fanned by conservative political organizations — promoters of Common Core have counted on teachers to be their best ambassadors and to reassure parents and students that the guidelines will lead to more thoughtful, rigorous instruction. 

Now, one of the biggest groups of educators in the country is on record saying it’s not working.