A pretty solid organized list of online resources that support science instruction from Digital Learning Environments– click HERE to see the list.
Here are three of my favorites mentioned:
Exploratorium
http://www.exploratorium.edu
This site was one of the first science museums to build a site on the World Wide Web. This site now contains over 15,000 Web pages exploring hundreds of different topics.Science NetLinks (K-12)
http://sciencenetlinks.com/lessons.php?BenchmarkID=9&DocID=111
The Thinkfinity partnership provides free, Internet-based content across academic disciplines. Science NetLinks’ role is to provide a wealth of standards-aligned resources for K-12 science educators, including lesson plans, interactive and reviewed Internet resources. Site features include Interactive Lessons, Resources, Benchmarks and Science Updates.PhET (Physics Education Technology) (9-12)
http://www.colorado.edu/physics/phet
This site from the University of Colorado has fun, interactive simulation of physical phenomena that make bridges to the real world. A collection of 40 Java applications for introductory physics is available.
Science for All 
I’m so excited technology is a big push in science education. I’m just starting my master’s work on teaching with technology, and I’m sure these links will come in handy! My students will love all the tools they can find on the internet to make their learning more fun!
Thanks!