Satellite indicates Flight 370 still flying seven hours after takeoff - The Washington Post
Excellent infographic about the search with colorful maps and explanatory visuals.
Malaysia officials open criminal inquiry into missing jet - New York Times
Good summary article with video and maps.
Finally, Slate.com has emerged with a more controversial, hypothetical theory that the plane may be somewhere in central Asia, an area known to harbor terrorist groups. The article raises several geopolitical issues that would be excellent for classroom discussion.