Wow- Science teachers take note. LearningScience.org is a great site. The site states that it is "a free and open learning community for sharing new and emerging tools to teach science". The tools range from interactive sites to video files. Some of them long, some of them short. One example of the tools would be Forces and Motion. F & M has 17 different listings of tools that you can use to teach the concepts. The main site lists all Science concentration areas. Seven different categories like Earth Science, Life Science, Science Inquiry, etc. I am sure that if you area Science teacher you have seen some of these sites before but never in one collection or "portal" if you will....I was surprised when I found and thought that you would enjoy browsing around (in all the spare time that teachers have :). Enjoy!