"The Smithsonian vowed that it would open up its digital collection by early 2015, Both the institution's Freer and Sackler galleries have posted over 40,000 pieces of global art online, all of which can be used for non-commercial purposes for free.
"Economics-games.com is a free educational games site for teaching microeconomics, industrial organization and game theory."
The Lionel Pincus & Princess Firyal Map Division is very proud to announce the release of more than 20,000 cartographic works as high resolution downloads. We believe these maps have no known US copyright restrictions.* To the extent that some jurisdictions grant NYPL an additional copyright in the digital reproductions of these maps, NYPL is distributing these images under a Creative Commons CC0 1.0 Universal Public Domain Dedication. The maps can be viewed through the New York Public Library’s Digital Collections page, and downloaded (!), through the Map Warper. First, create an account, then click a map title and go. Here’s a primer and more extended blog post on the warper.
"Six awesome courses in one awesome channel: John Green teaches you US History and Hank Green teaches you Chemistry. Check out the playlists for past courses in World History, Biology, Literature, and Ecology."
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