might provide some guidance to states, not on the content of their science standards, which they are prohibited by law from doing, but on the nature and characteristics of well-formulated science standards. We note here that this discussion relates primarily to content standards; issues specific to achievement standards are discussed at the end of the chapter.

In a standards-based accountability system such as NCLB, content standards are the explicit reference point for action. Rather than serving as loose guides, content standards must be a consistent reference point, as the U.S. Constitution is for the nation’s judicial system. State content standards define what students should know and, therefore, what teachers should teach. They also are used for developing assessments and setting achievement targets that will be used to judge student achievement, identifying successful and unsuccessful schools and districts, reporting to the public, triggering interventions (including reorganizations and reconstitutions), and issuing sanctions and rewards. In addition, standards are the reference point for developing improvement strategies to enhance curriculum and instruction and to make school and district operations more effective. Although science is not currently included in the NCLB accountability requirements, it may be in the future; moreover, states may use results from science assessments for their own accountability purposes. The committee assumes that because the results from state science assessments will be publicly reported, they will become part of the accountability system, even if the results are not included in calculations of adequate yearly progress.

The committee has compiled a list of characteristics that science content standards should have. Science content should:

• be clear, detailed, and complete;

• be reasonable in scope;

• be rigorously and scientifically correct;

• have a clear conceptual framework;

• be based on sound models of student learning; and

• describe performance expectations and identify proficiency levels.

Each of the characteristics is described below, and examples of current state standards are used to illustrate many of them.⁵ We were unable to identify any complete set of state science standards that meets all of the criteria we describe. We did, however, find examples of standards that embody one or more of these