This is one of five panel reports that have been prepared as part of the first phase of Project 2061, a long-term, multipurpose undertaking of the American Association for the Advancement of Science designed to help reform science, mathematics, and technology education in the United States. Major sections included are: (1) "Introduction" (describing the nature of physical science, information science, and engineering); (2) "Social Interactions"; (3) "Methods"; (4) "Models and Measurement"; (5) "Unifying Concepts" (including the concepts of materials, energy, information, and systems); (6) "Key Specific Concepts" (providing concepts in the area of physics and chemistry, earth and astronomical sciences, information science and computer science, and engineering); and (7) "Notes on Learning" (suggesting ideas on teaching). The members of the panel and consultants are listed. (YP)