The Common Core national education standards are deeply unpopular with conservatives and left-leaning teachers unions. But since it's not a wedge issue, the Democratic Party has no idea how to exploit it for political gain.
Instead, the party is simply ignoring Common Core altogether, according to internal emails recently leaked by Wikileaks. Eric Walker, a communications director for the DNC, explicitly told staffers that they "should not be touching it at all." Here's the relevant section of his email:
Common Core is a political third rail that we should not be touching at all. Get rid of it.
Most people want local control of education so having Cruz and Trump saying it on a DNC video is counterproductive. Would get rid of any references to that.
Common Core was a bipartisan reform first backed by the Bush administration and enthusiastically pushed by the Obama administration, which incentivized the states to adopt it. The standards themselves were birthed by the Bill and Melinda Gates Foundation. The goal was to create a set of universal math and English standards, but critics contend that Common Core essentially creates a national curriculum—one that has been very poorly implemented.
Conservatives don't like to cede control over educational matters to the feds. But a lot of liberals don't like Common Core, either. That's because it requires teachers to prepare students for high-stakes standardized testing, which they claim undermines their autonomy within the classroom.
Donald Trump has promised to put an end to Common Core. Some states that have formally backed out of the standards actually continue to abide by them—they just don't refer to it as Common Core. Hillary Clinton, on the other hand, supports Common Core, though it's clear we won't hear her talk about it anytime soon.