A fight is erupting in the New York state legislature over reforming how teachers are evaluated. 

Virtually both chambers agree in the Senate and Assembly that teacher evaluations should be decoupled from state tests. But Senate Republicans also want to strengthen charter schools, predominantly in New York City. It's a linkage the Assembly opposes.

"We're not looking to load it up with other things, particularly other things the conference is not interested in doing," said Assembly Speaker Carl Heastie. "If the Republican conference wants a permanent change, they can just pass the bill that we passed."

The decoupling bill has been approved in the Assembly, and it's a measure the state teachers union is endorsing. It would gut a key education reform championed only several years ago by Governor Andrew Cuomo.