It's not just parents and teachers blasting Common Core standards anymore.

Members of the Board of Regents and leaders in the State Senate and Assembly are quaking and defecting as they confront a statewide grassroots revolt.

They want implementation slowed or postponed.

But most of the changes can't be slowed or postponed. They would have to be reversed. And then what? Nobody has a good answer to how kids might be taught and tested, and how teachers might be evaluated.

Curricula based on a Common Core were adopted in 2010. They've been the statewide standard for 1½ years. And no other lesson plans are waiting in the wings.

The standardized tests students are scheduled to begin taking are based on skills they've been studying during this time. To forgo those tests, and the teacher evaluations that come with them, would not be acceptable.

What a blunder to abandon the higher standards and the accountability our schools so urgently need. Nationally, 45 states have adopted Common Core. Not one is retreating.

But in New York, the system of testing and teacher evaluations was negotiated and championed by the state and the teacher unions that are leading the fight against them.

The unions oppose any standards-based teacher ratings and any removal of obstacles to getting rid of the least competent teachers. Their strategy was to accept a deal on evaluations, then fight its implementation at every step.

The education establishment has fueled a separate worry among parents over lower student test scores.

But while they had a valid gripe earlier about the slow initiation of Common Core curricula, the state should be caught up by year's end. As schools Chancellor Carmen Fariña said, testing isn't the issue. Common Core is the way to go. It just hasn't been implemented well.

A Regents panel will report Monday on suggested reforms.

Yet much of the controversy depends on the way Gov. Andrew Cuomo responds. He must stifle election-year temptations to accede to pressures from nervous parents and fight instead for the best interests of our students.