Georgia Public Broadcasting Education Video - Storage site for all videos from GPB Education (satellite streaming to public schools only), Discovery Education, and others. It is a searchable K-12 site.
Encyclopedia Britannica Online School Edition has full encyclopedia access, lesson plans, elementary and high school learning activities, and access to other research sources. Use this and send me feedback. If you like this, there are other sites such as American History Annals and Original Sources that we can get access to.
Rosetta Stone is the best foreign language source available. It is highly recommended by Educators and Home Educators. If you register for the Homeschool on-line version, you get 1:1 live tutoring. Great value for the price you pay.