The National Education Association is seeing increased opposition to Common Core among its members, though a majority still support the move toward state standards in English and math.

In a September survey of 1,200 NEA members, 75 percent were found to be at least somewhat supportive of Common Core. Just 11 percent of respondents said at the time they were opposed.

In a much broader poll of nearly 17,000 NEA members in 33 states and conducted at roughly the same time, however, more than a quarter of union members were opposed to Common Core.

That study found 71 percent of NEA members supported Common Core, while 29 percent were opposed.

The second study was obtained by Mike Antonucci of the Education Intelligence Agency, an organization that researches the inner workings of teachers unions.

The higher opposition rate may be the result of fear over teacher evaluations. Antonucci wrote earlier this week that teachers don't trust others to evaluate them.

“Teachers have seniority provisions in their contracts — a measurable factor — because they don’t trust administrators to use unmeasurable and subjective means to evaluate them,” Antonucci said. “On the other hand, teachers also distrust a host of measurable factors that might be used to evaluate them, most notably student test scores.”

Antonucci, a critic of teacher’s unions, pointed to a survey in Providence, R.I., of three candidates for president of Providence Teachers Union. Each one was asked whether teacher evaluations should be tied to student success and if not, how they would measure success.

Each one gave a very different — and vague — answer.

“If unions could defend their position on teacher evaluations with something that includes students, they might win some support,” Antonucci concluded.