This summary outlines the National Science Education Standards, the guidelines which define the science content that all students should know and be able to do and which also provide guidelines for assessment of student understanding of the content. This document contains a definition of the National Science Education Standards, a rationale for the standards, background information on who developed the standards, the guiding principles of the document, an explanation of current thinking on how students learn science, a discussion of scientific literacy, a comparison of these standards with the Benchmarks for Science Literacy from the American Association for the Advancement of Science (AAAS), details of the content standards in chart form, an outline of the professional development standards for science teachers, a description of the characteristics of an effective school science program, and a description of the systemic support required for effective reform of science teaching and learning. (DDR)