a.) common core - the idea that there is a base body of knowledge to which all students should be exposed, whether schooled in California, Massachusetts, North Dakota or Florida
b.) standardized testing - the idea that there should be one method, consistently designed, delivered and evaluated, for measuring students mastery of a.)
c.) teacher/school evaluation - the idea that there should be some objective scale by which communities can determine if teachers are doing their jobs well or poorly
For the record, I endorse a.) but wonder about b.) and c.), mainly because I believe there are many non-academic, social conditions that affect their outcomes.