This is an assessment framework, not a curriculum framework. In broad terms, this framework attempts to answer the question: What mathematics should be assessed in 2009 on NAEP at grades 4, 8 and 12? The answer to this question must necessarily take into account the constraints of a large-scale assessment such as NAEP, with its limitations on time and resources. Of critical importance is the fact that this document does not attempt to answer the question: What mathematics should be taught (or how)? The framework was developed with the understanding that some concepts, skills, and activities in school mathematics are not suitable to be assessed on NAEP, though they may well be important components of a school curriculum. An example would be an extended project that involves gathering data, or a group project.