A summary from a report published by The Fordham Institute:
The common core math standards have been proven to be less rigorous, less clear, and more in number than our former standards. The Thomas B. Fordham report evaluated both the common core and Indiana’s former standards and came to the following conclusion:
INDIANA GRADE A, Clarity and Specificity: 3/3 Content and Rigor: 7/7 Total State Score: 10/10
COMMON CORE GRADE A-, Clarity and Specificity: 2/3 Content and Rigor: 7/7 Total Score: 9/10
The Bottom Line With some minor differences, Common Core and Indiana both cover the essential content for a rigorous, K-12 mathematics program. That said, Indiana’s standards are exceptionally clear and well presented. Standards are briefly stated and often further clarified with the use of examples, so they are considerably easier to read and follow than Common Core. In addition, the high school content is organized so that the standards addressing specific topics, such as quadratic functions, are grouped together in a mathematically coherent way. By contrast, the organization of the Common Core is more difficult to navigate, in part because standards on related topics sometimes appear separately rather than together.