Problem #1 with CC:
"Progressive educator John Dewey argued for standardized curriculum to prevent one student from becoming superior to others and envisioned a workforce filled with people of “politically and socially correct attitudes” who would respond to orders without question."

Problem #2 with CC:
"Relativism’s influence on the Common Core is evident in the open-ended and research-based assessment questions and the expansive new student tracking systems, ideas which have been strongly promoted by relativist Howard Gardner."

I actually saw Howard Gardner at one of his presentations a couple of months ago and asked him some questions on how passion, open source, and learning will/should figure in education. He didn't have much of a response. Well, he's a bit dated imo. You need passion or emotions to remain engaged and motivated in learning. This is a HUGE problem with education today.

Problem #3, #4, and more with CC:
Common Core was developed based on business and policy wonks. There's little in terms of digital citizenship or global citizenship. American exceptionalism still reigns. I'm a former history teacher/professor and I'm not saying that it's not worthwhile to learn about US History. What I am saying is that digital technology has changed the parameters in our worldview and this should be reflected in any school curriculum. At the moment, I am not convinced this is the case with CC.

Common Core was also developed with the fallacy that America needs to ensure everyone is college-ready or prepare everyone for a college education. This is foolish for many, many reasons.

"The Common Core standards require students to master a checklist of skills every year." That's dumb. That assumes every student is on the same trajectory and develops at the same rate as everyone else. This is totally false. What happens to the late bloomer who doesn't read by 2nd grade or what happens to the advanced learner who is reading college textbooks by 2nd grade?

"The final argument—standardization—hinges on the premise that one textbook, or just a few aligned with the Common Core, would be an improvement over the numerous and varied textbooks available today. " - Um, yea. Don't get me started on standardization or textbooks. How about those high school history textbooks that are written at a 5th grade level? Do they remain with CC or do they get finally ditched?

But like I said, there are many reasons why I don't think CC will be beneficial for most children.