I’ve been one of the SciLinks “webwatchers” for quite a few years. As we review new sites to include in the database, each site is correlated to a specific keyword and grade level (such as K–4 Fossils, 5–8 Cardiovascular System,  9–12 Properties of Sound). But sometimes, we find large collections of activities on science-related topics. Although we align individual activities with specific SciLinks keywords and submit them to the database, the entire collection may be of interest to teachers planning instructional units.
These are not simply a list of someone’s favorite sites or activities. These are activities, simulations, multimedia collections, and informational pages created by organizations or institutions as part of an outreach program or related to their projects and research. You can search the sites by grade level and subject area. Here are some examples of these collections:

• ARKive describes itself as a “multimedia guide to the world’s endangered animals, plants, and fungi.” The graphics are stunning and include both photographs and videos.
• The Molecular Workbench has many interactive simulations and includes topics in science and engineering. Use the “Software” link to download the software and get a list of available simulations. The “Curriculum” link leads to a database of lesson plans that use the simulation. The lesson plans include objectives, key concepts, and correlations to popular textbook chapters.
• You and your students could spend hours browsing the Windows to the Universe site, sponsored by the National Earth Science Teachers Association. The site now has ads on it, which can be eliminated with a modest membership fee (for teachers, this also includes access to additional classroom resources). Spanish versions of the topics are also available, and the topics have beginner, intermediate, and advanced levels.

• Use the Vision Learning Library to find modules on a variety of topics in biology, chemistry, physics, and science processes. Each module, written by an expert, includes text, graphics, animations, and a quiz. You can register (free) to create your own classroom space on the site. The library is also available in Spanish.
• Brightstorms is a collection of brief videos (< 5 minutes) on a variety of topics in biology, chemistry, and physics. The videos consist of a teacher “lecture.” The site mentions homework help, but the videos could also be used for supplementary work, alternative explanations, or review.
• In addition to all of the NOAA resources check out the c.o.o.l. Classroom from Rutgers University. There are many resources related to oceanography, specifically the Atlantic.
• Explore has on-line exhibits, lesson plans, and information from the Exploratorium Museum in San Francisco. There are activities for students of all ages and resources for classroom implementation.
• Cool Science from the Howard Hughes Medical Institute has virtual labs, videos, and “BioInteractives” with in-depth investigations and information.
• You can search the index of PhET simulations by science content area or by grade level. Each animated simulation has teaching ideas and could be used by individuals or small groups or projected to a whole class.
• NIH Curriculum Supplements for high school, middle school, and elementary grades are lessons and activities that help students understand the science behind health topics such as bioethics, genetics, and the brain.