All of these resources provide an excellent overview of general reference material.
DK Find Out!
Check out the beautiful images and clever way they have presented the information.
Ask the Experts
Awesome Library - K-12 Education Directory
Facts Subject Index - Refdesk
Provides 24 resources for reference categories.
How Stuff Works
Describes the composition, function and appearance of hundreds of items.
Internet Public Library
A great online library reference
A great way to find both fun stuff and information for completing your homework assignments.
Web guide and search tool for kids by librarians.
LibrarySpot - a virtual library resource center