University of Wisconsin
University of Wisconsin: The Constellations and Their Stars
An excellent site dedicated to the constellations and information about the objects which make them up. Contains a great deal of information about various stars, galaxies and other objects, as well as details on how best to observe them.
University of Michigan
University of Michigan: The Big Bang It Sure Was Big!
A detailed examination of "what is known about the Big Bang itself, the age of the universe, and the synthesis of the first atoms."
Other
Constellations Web Page: The Constellations
Information about 88 constellations, including the myths associated with them and details of the major astronomical objects that are part of them.
University of California
Uc Berkeley: At Home Astronomy: The Size and Distance of Planets
In this activity, "You will investigate the concepts of relative size and distance by creating a basic model of our solar system." Planet printouts are provided and this site contains related links.