approval” on specific curricula or providing a report card, as others have done for state standards or tests (U.S. Department of Education, 1999; Achieve Inc., 2002). This decision was deliberate. As a committee of the National Research Council of The National Academies, our primary contribution was to clarify the phrases scientifically valid evaluation study and scientifically established as effective in the context of K-12 mathematics curricula. Such an analysis can elucidate the current knowledge of how these curricula were evaluated and help decision makers avoid judgment errors that are likely when the completeness or scientific rigor of evaluations of such materials is misunderstood.

Recognizing the complexity of judging curricular effectiveness, this report is designed to assist future evaluators and policy makers in designing and conducting evaluations that provide accurate, comprehensive, and valid advice to decision makers and practitioners on the efficacy of curriculum materials. Our primary goal was to advise our audiences on what could be learned from these initial efforts and how lessons learned, strategic decisions, adaptations in method, errors and weaknesses, and tentative patterns of results could further future evaluation efforts and decision making on curricular policy.

The following 13 mathematics curricula programs¹ (The K-12 Mathematics Curriculum Center, 2002) were supported by the NSF, and the evaluations of these materials were reviewed by our committee:

Elementary School:

• Everyday Mathematics (EM), Grades K-6 (SRA/McGraw-Hill)

• Investigations in Number, Data and Space, Grades K-6 (Scott Foresman)

• Math Trailblazers, Grades K-6 (Kendall/Hunt Publishing Company) Middle School:

• Connected Mathematics Project (CMP), Grades 6-8 (Prentice Hall)