I did want to re-introduce you to PBS Learning Media. In order to save you time signing up, last year i created a collective account with firstname.lastname@example.org with as the username and schenk027 as the password.
PBS Learning Media has school ready digestible chunks of information from PBS content organized by curricular subjects such as math, language, science, social studies. It is a great resource for finding relevant content that complements an ongoing lesson.
If you want to sit back, make some popcorn, and enjoy longer chunks of content, give ECB Video Link a try http://goo.gl/wCPrG. The content here are full version of some of PBS' older content that would be most pertinent to older elementary students.
A new content source from the ECB family of services is Digital Science Online. This site is very science focused with emphasis on the physical, life,and earth sciences.
Taken together these three semi-distinct ECB services offer us a solid source of educationally related content. If you have not taken a look, it might be worth the time. Remember to use the log on information above or create your own.