Common Core’s primary backers have been assuring us for years that the standards do not mandate any specific curriculum or prescribe any particular method of teaching. However, now that states have begun to implement Common Core, those same backers are singing a different tune. Professor Jay P. Greene highlighted the shift at the Education Next blog. For example, just six months ago, prominent Common Core supporters Kathleen Porter-Magee and Sol Stern wrote in National Review Online:

Here’s what the Common Core State Standards do: They simply delineate what children should know at each grade level and describe the skills that they must acquire to stay on course toward college or career readiness. They are not a curriculum; it’s up to school districts to choose curricula that comply with the standards.

However, now Porter-Magee and Chester Finn of the Fordham Institute argue that the standards must change “classroom practice”:

In order for standards to have any impact, however, they must change classroom practice. In Common Core states, the shifts that these new expectations demand are based on the best research and information we have about how to boost students’ reading comprehension and analysis and thereby prepare them more successfully for college and careers. Whether those shifts will truly transform classroom practice, however, remains to be seen.

What sort of changes will that entail? Well, for one, Common Core uses “lexiles,” which measure things like sentence length and vocabulary to rate the complexity of a text, to determine which books are suitable for each grade level. As Professor Blaine Greteman points out at The New Republic, the simplistic lexile scores absurdly conclude that “The Hunger Games” is more complex than “Grapes of Wrath” and that Sports Illustrated for Kids is more complex than “To Kill a Mockingbird.” Greteman concludes, “Lexile scoring is the intellectual equivalent of a thermometer: perfect for cooking turkeys, but not for encouraging moral growth.”

As Greene notes, the change in tune concerns not only the impact on curriculum, but also whether Common Core prescribes a given manner of teaching:

The National Council on Teacher Quality, with support and praise from the Fordham Institute, are grading teacher training programs on whether “The program trains teacher candidates to teach reading as prescribed by the Common Core State Standards.” Wait. ”Prescribed?” I thought Common Core didn’t prescribe pedagogy. But that was back when I was young and we were dating.

It would be nice if Fordham and others trying to hold down the right flank of the Common Core advocacy campaign could keep their story straight. The switch once the fight has shifted from adoption to implementation creates the impression that these folks make whatever argument they think will help them prevail in the current debate rather than relying on principle, evidence, and intellectually serious policy discussion.

[Hat tip to Greg Forster of the Jay P. Greene Blog for the title of this post.]