This project will produce assessment materials for mathematics instruction K-12 that have broad national applicability -- and that serve not only as a means of measuring student attainment, but also as a positive force for curriculum change. The project will have several kinds of product: o assessment packages for each of three grade ranges that exemplify national goals and related state guidelines - high quality, practicality, and balance in terms of nationally agreed curriculum objectives for mathematics (e.g. those in the two volumes of NCTM Standards); o explicit curriculum support, including both classroom materials and professional development resources, to facilitate the transition, enabling typical teachers to prepare their students to tackle effectively what are initially new kinds of task before they take on comprehensive new curricula; o active collaborative links between the assessment designers and those concerned with the design and delivery of curricula -- national curriculum development projects, the professional associations, states and others who have similar curriculum objectives; and o a driving force for curriculum enhancement through the pressures on the curriculum generated by this assessment, which will forward national curriculum objectives. These products will be developed at three national sites (in California, Massachusetts, and Michigan) and the Shell Centre, in active collaboration with NSF-supported curriculum projects and the related State Departments of Education.