I had never used this site before, but I really like the kid's field trip to Mars. http://www.kidscosmos.org/kid-stuff/kids-mars-trip-site-map.html. I like that it can be used to compare and contrast Mars and Earth. it is meant to be used by grades 2-8.

Great links for science and technology sources. I don't have a science text and I use this site all the time for my students.

Lots of resources for teaching and the price is right. It won best blog and resource sharing site in 2009 from Edublog.

A wonderful source for teachers on how-to, uses of, and just about anything you want to know about digital storytelling. It is especially useful for writing and social studies.