iTunes U has started K-12 offerings available as of July 1st, 2008.
The best one I've discovered for D.S.T. is the Maine Writing Project. 7th and 8th graders, with their laptops are writing and creating digital stories about "Place". There are 10 topics for stories currently. In each segment students read their stories. An adult narrator sometimes accompanies the stories. All the stories make up an "electronic anthology" of rural Maine.
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