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Physics, Astronomy, and Physical Science Research Guide: Astronomy sites
a collection of digital resources for college-level introductory astronomy faculty and students. Produced by the the American Astronomical Society, the American Assn. of Physics Teachers, and the NSF-NSDL.
Earth Revealed is a video instructional series on Earth science and astronomy for college and high school classrooms and adult learners; 7 one-hour video programs, from Annenberg.org. Create a free account and watch at your convenience!