Get Body Smart - online exploration of human anatomy
Inner body - Macro and micro anatomy lessons
Learning Science - A free and open learning community for sharing newer and emerging tools for teaching science
DNA Origami - build a DNA strand
Earthquakes for kids - The information is official and detailed, and the site is up to date.
Science Update - Amidst some fun, these audio clips provide a regular dose of news about current scientific research.
Google Idea Springboard - get tons of ideas
Science Buddy - An impressive help guide that gives meaningful help for great science and engineering projects, as well as support for successful fairs.
Science Snacks - hands-on, teacher-tested, and use cheap, available materials.
Science Bob -A well-rounded, fun place to explore science activities.
Interactive Sites for Education
Explore Learning (Gizmos)
Interactive Simulations - PHET
How Stuff Works - Tons of science videos with thought provoking questions.
Open Culture - 125 great science videos
Algodoo - physics
Tinkerbox