As a retired teacher, having taught in several states over many decades, in all grades and areas, including Special Ed, RSP, and GATE (gifted GT, etc.) I cannot view this as a good thing. It was not always thus, as they say, and before 2010, standards in different schools, different districts, and different states used to vary wildly. Even standards in the same school were not often consistent.
The basic intent of the common core idea is to provide a framework for what is taught at each grade level; “It details what K–12 students should know in English language arts and mathematics at the end of each grade.” Standards in other areas were added later, some nationally and some by individual states, but most dove-tail with the nation-wide standards.
https://en.wikipedia.org/wiki/Common_Core_State_Standards_Initiative (Lots of info here.)
You certainly know that the body of knowledge children must master in school increases every year. In fact, “It is generally believed that the world’s knowledge increases logarithmically, i.e., every ten years the amount of knowledge doubles.” http://www.peavinequarter.com/guest-columns/education-and-the-information-explosion/ So you can understand why it might be useful to outline the basic concepts to be taught at each grade level. Teachers can know that (in an ideal world) students coming into his or her grade have covered certain vital areas, and can then proceed to work on the next level’s goals instead of going back to re-visit something because another class “just didn’t have time,” or decided to skip something.
Logically, when you have set out goals and objectives, there needs to be a way to measure levels of progress and achievement, as well as areas of concern. That means tests. In my experience, no one likes them; not teachers, not students, not parents, and maybe not even administrators. But they are necessary for accountability, if nothing else, and can help teachers design their instruction as well as help identify students (and maybe even curriculum) that might need help. Plus, testing should and is changing to be made more appropriate, valid and useful all of the time.
If you don’t know or understand about standards and tests, call your district. Volunteer to join a parent group, speak up. The information IS out there, you just have to find and use it. This is an excellent site in California: http://capta.org/focus-areas/education/common-core/
However, the “parent” group that supports the anti-core sentiment (similar in my mind to the anti-vaxers), Parents Against the Common Core, is part of American Principles (NOT principAls) in Action - a conservative group "dedicated to preserving and propagating the fundamental principles on which our country was founded..." http://www.politifact.com/personalities/american-principles-action/, and committed to “full power conservatism”. http://www.wnd.com/2011/02/259869/ If this is your “thing” then fine. But if you can read between the lines to see a huge, hidden agenda, then you may want to do some research f your own. Research other than on Facebook, that is.
The good news is that school districts in my experience have been open to change, and have held discussion and debates on ideas, with the goal of improving instruction, student progress, teacher abilities, as well as understanding and resources for students, parents, teachers and schools.
So I ask thinking people to do just that: think and read. Virtually all states and districts now have their core standards available on line. Check it out. I don’t know where Franki Pagan (a commenter on Facebook) lives, or what her school is like, but if it is a public school, and she doesn’t think they are teaching math skills anymore, she must be on another planet.