U.S. News and World Report points out that the rationale for Common Core and its tests was that parents needed to know how their child compared to children of the same age in other states.

But with two different testing consortia, and with so many states dropping out of those consortia, the rationale has been eviscerated.

Frankly, it never made any sense to argue that parents everywhere were hungering to compare their own child’s test score to children in other states. Maybe it is just me, but I never met a parent who said, “I’m desperate to know how my child’s test score compares to children in the same grade in Alaska and Maine and Florida. And to insist that having this information would somehow improve education or benefit students made no sense either. What we learn from standardized tests is that family income matters. Having the same test everywhere doesn’t change that fact. What if the same energy had done into reducing poverty and segregation? We might have made a dent. Instead, our whole country is pointed to the wrong goals.

Says U.S. News:

Even when all the results are available, it will not be possible to compare student performance across a majority of states, one of Common Core’s fundamental goals.

What began as an effort to increase transparency and allow parents and school leaders to assess performance nationwide has largely unraveled, chiefly because states are dropping out of the two testing groups and creating their own exams.

U.S. Education Secretary Arne Duncan told state leaders in 2010 that the new tests would “help put an end to the insidious practice of establishing 50 different goal posts for educational success.”

“In the years ahead, a child in Mississippi will be measured against the same standard of success as a child in Massachusetts,” Duncan said.

Massachusetts and Mississippi students did take the PARCC exam this year. But Mississippi’s Board of Education has voted to withdraw from the consortium for all future exams.

“The whole idea of Common Core was to bring students and schools under a common definition of what success is,” said Tom Loveless, a senior fellow at the Brookings Institution. “And Common Core is not going to have that. One of its fundamental arguments has been knocked out from under it.”

However, if you want to compare state performance, you can always look at the National Assessment of Educational Progress, which has been comparing states since 1992. NAEP also compares a score of urban districts every other year.