If standards are well written, they become the rudder of education, and effective methods of instruction and assessment will follow in its wake. If the standards are not well written, whether or not the content is there, assessment becomes the rudder, with instruction following in its wake – especially when the standards are written in such a way as to lend themselves to multiple interpretations, not of the content, but of what is expected of students. Well written standards lend themselves to good assessments. Poorly written standards lend themselves to poor or meaningless assessments. We have already experienced poor and meaningless assessments across the country.
From The Coalition for World Class Math’s Comments on the Common Core Standards for Mathematics.