The Teaching Channel has a rich collection of K-12 video lessons and tools for all teachers. You will also find a variety of video lessons that would be useful for K-12 science instruction. Click HERE to see videos related to science.
The video lessons include topics such as classroom management, differentiated instruction, engagement, etc. Definitely worth adding to your bookmarks!
See the embedded Welcome to the Teaching Channel video and Content Differentiation in 3rd Grade Science below…
Science for All 
Hi Kirk,
Thank you for posting about Teaching Channel! We really appreciate your help in spreading the word about us.
We have added some new tools and resources on our website that you should check out – a blog featuring the 2010 National Teacher of the Year, and a webpage where you can learn 5 Great Ways to use the Teaching Channel website. We also have a lesson planner tool and all of our videos are downloadable and embeddable.
Thanks again for mentioning us!
Julia Chope
Community Coordinator at Teaching Channel
My pleasure.. what a wonderful resource you have assembled. There are now several great online sites that provide video of classroom instruction (this is needed and wanted in the field). Let me know how I can help.
Kirk