City results on state math and reading tests plummeted last year – confirming warnings that testing kids on tougher educational standards would shock the school systems from New York to Buffalo.

Fewer than 30 percent of public school kids in grades 3 to 8 passed the state math exams last year, while roughly 26 percent passed the exams in reading, according to the Wall Street Journal.

That’s down from pass rates of 60 percent in math in 2011 and 47 percent in reading.

The poor results were prompted by New York’s adoption of higher learning standards known as Common Core, which was embraced by 44 other states and Washington D.C.

But New York was one of the few states to have already changed its exams to reflect the new standards – meaning kids, teachers and principals had less time to prepare to meet the higher benchmark.

In fact, city schools won’t even begin teaching a curriculum that’s fully-aligned with the new standards until the coming school year.

“It wouldn’t have made any sense to give assessments this year based on old standards, while expecting teachers to teach to the Common Core,” said State Education Commissioner John King, who referred to the humbling results as a new “baseline” for whether kids are on a trajectory to succeed after high school.

U.S. Education Chief Arne Duncan got on a conference call with NY reporters yesterday to emphasize that the pending results – though expected to be dismal – were essentially righting a wrong.

In a harsh assessment, he blasted school systems across the country with having dumbed down standards for years while “lying” about how well their students were doing.

“They said children were on track to being ready for college and careers when in reality, they weren’t even close,” he said. “Finally, we’re telling them the truth, we’re telling their parents the truth and we’re telling their future employers the truth.”