Americans agree that our students urgently need better science education. But what should they be expected to know and be able to do? And can the same expectations be applied across our diverse society? These and other fundamental issues are addressed in "National Science Education Standards" - a landmark development effort that reflects the contributions of thousands of teachers, scientists, science educators, and other experts across the country. "The National Science Education Standards" offer a coherent vision of what it means to be scientifically literate, describing what all students regardless of background or circumstance should understand and be able to do at different grade levels in various science categories. The standards address: the exemplary practice of science teaching that provides students with experiences that enable them to achieve scientific literacy; criteria for assessing and analyzing students' attainments in science and the learning opportunities that school science programs afford; the nature and design of the school and district science program; and the support and resources needed for students to learn science. These standards reflect the principles that learning science is an inquiry-based process, that science in schools should reflect the intellectual traditions of contemporary science, and that all Americans have a role in improving science education. This document will be invaluable to education policymakers, school system administrators, teacher educators, individual teachers, and concerned parents.