Astronomy Online, 6-12

http://astronomyonline.org/
This web site is arranged into broad categories: Observation, Science, Solar System, Stars, Our Galaxy, Cosmology, Astrobiology, Exoplanets, and Astrophotography. Each main category is grouped into sub-categories that cover such topics as constellations, astronomy tools, the solar system formation, stellar evolution, and more. Each of the topics includes a number of informative and illustrated essays with embedded links that lead to more information. Check out the Astrophotography section to see some professional photographs from the Canada-France-Hawaii Telescope at the top of Mauna Kea and some amateur images of the solar system, star clusters, nebulae, and more.