American Museum of Natural History: The American Museum of Natural History website. It provides an absolute treasure trove of information in text, photographic, and multimedia form.
ARKive.org: Is a multimedia repository and guide to the world's most endangered species, which was created with the help of the foremost environmental filmmakers, photographers, conservationists, and scientists.
BEN: BEN is the National Science Digital Library (NSDL) Pathway for biological sciences education. The BEN Portal provides access to education resources from BEN Collaborators and is managed by the American Association for the Advancement of Science (AAAS).
Carbon Dioxide Information Analysis Center: The Carbon Dioxide Information Analysis Center is the primary climate-change data and information analysis center of the U.S. Department of Energy. The website provides a wealth of data and also access to all the raw information to all things climate change related.
Chem1 Atoms and the Periodic Table: This is an online textbook designed to provide a thorough, in-depth treatment of physics at a first-year college level.
Darwin Manuscripts Project: A digital representation of Darwin's work on evolution, with scholarly commentary, put together by the American Museum of Natural History.
Energy Information Administration: The U.S. Energy Information Administration (EIA) is an agency of the federal government that specializes in the collection, analysis, and dissemination of energy information to the public and policy makers alike.
European Space Agency: The homepage of the European Space Agency which provides a wealth of science information on/about earth and beyond.
Exploring Life's Origins: The origins of life website present its material in an animated format to make the complicated science of evolution easier to understand.
Information Systems for Biotechnology: Information Systems for Biotechnology provides information and resources to support the environmentally responsible use of agricultural biotechnology with an emphasis on genetically engineered plants and organisms.
Math Digital Library: A multifunction, multidisciplinary website that focuses on math distance learning and it maintained by the Mathematical Association of American and the National Science Digital Library.
NASA: The National Aeronautics and Space Administration is the U.S. Government's premiere space science agency. The website provides a literal wealth of scientific and technical data about earth, the solar system, and our place within the cosmos and what's out there.
National Agricultural Library Catalog: The National Agricultural Library Catalog (AGRICOLA) provides citations for all USDA funded research.
National Biological Information Infrastructure (NBII): The National Biological Information Infrastructure is a collaborative program to provide access to the nation's data/information on biological resources.
National Center for Environmental Health: The CDC's National Center for Environmental Health websites provides a wealth of information to the public about all aspects of environmental health and how it affects the public.
National Wildlife Health Center: The National Wildlife Health Center is a science center for the United States Geological Survey. Established in 1975 the NWHC servers as the premiere biomedical laboratory dedicated to assessing the impact of disease on wildlife and identifying the role of various pathogens in contributing to wildlife losses.
Periodic Table Live!: This interactive periodic table provides a wealth of information about the elements, their properties and reactions and history.
Scitopia.org: A federated search portal that was created through the collaboration of 21 leading science and technology societies to allow for the searching of science and technology related publications.
Species 2000: The Species 2000 project goal is to catalog every single organism on earth and provide a usable search interface to get information about those organisms.