We just found this excellent white paper on the background of Common Core, and a look at the standards themselves which was posted at Truth in American Education. While it is long (44 pages), you might want to read it if you have a chance. There is a lot of factual information with endnotes at the back to direct you to the sources.
Controlling-Education-From-the-Top-PRINT, May 2012. This 23 page white paper written by Emmett McGroarty and Jane Robbins and published by American Principles Project and the Pioneer Institute.