PHet - These are interactive simulations from the University of Colorado in Boulder. They include a large selection of simulations in biology, earth science, physics, chemistry, and math. On a Teacher Page you can browse for teacher created activities that go with a simulation. Best of all you can download simulations to a local computer if you do not wish to rely on an internet connection.

OnlineLabs - Serves as a comprehensive, encyclopedic reference about online labs in a variety of subjects, particularly virtual laboratory simulations for science education. We categorize useful listings for online lab simulations, virtual science experiments and free educational software.Feature resources in Chemistry, Physics Biology, Anatomy, Geology, Astronomy, Design and help learners identify free and commercial virtual science labs.Students get hands-on science and math experiences without having to set foot in a physical classroom or laboratory environment.

iLabCentral- Making high school science labs more real, more engaging, and more accessible. Online laboratories (iLabs) are experimental facilities that can be accessed through the Internet, allowing students and educators to carry out experiments from anywhere at any time. Explore an entire unit that allows students do perform tasks that may never be done in your high school.

Web Based High School Chemical Simulations

Science Netlinks- Providing a wealth of resources for K-12 science educators, Science NetLinks is your guide to meaningful standards-based Internet experiences for students.

Fermilab - Especially interesting is this series or games and simulations.

Nobel Prize Games-'s educational section consists of 46 productions. Of these, 29 are interactive learning games of various sorts and degrees of difficulties. Most of them also includes a "Read more" about the subject and enjoy learning.

Vital Lab - Small Collection of Science Flash Simulations.

Med Mysteries - Interactive learning adventures teaching the scientific method and microbiology.

Anatomy - Nice simulation for working with and getting to know the parts of the human body.

Cells Alive - Video and lessons that apply to the Cell. Very engaging with some outstanding information.

Chemistry Timeline - Learn about chemistry through out history.

Chalkbored - Lessons in Chemistry for grades 11 and 12

Chemistry Search Engine - A search engine that searches through 250 approved chemistry sources.

What Is In It? - Great to stress literacy across the science curriculum. Learn what is in certain items. Great chemistry lesson in it self.

The Science of Baseball - Great literacy site with some outstanding simulations. Not only that... baseball can be very engaging!

Skateboard Science - If baseball doesn't help engage... then skateboarding might. Excellent place for common core literacy.

Fault Line - A great place to read, try activities, and learn about earthquakes.

Explore - Awesome sites to explore from the Exploratorium involving all areas of science.

Seeing Science - Unique interactive science resources for secondary education.