(Recommendation from Courtney Phillips and her students who found our web page, thank you so much for the great resource)
ipl2 for Kids is a section of the huge Internet Public Library experimental resource, which is created and maintained by professors and students at library and information science programs. The site is organized by subject and does link to other sites. It may be a bit too cluttered for younger students to find what they're looking for on their own, but for older students, parents, and teachers, it's a well-stocked resource. Kids can submit a question (barring medical, legal, tax, and personal opinion) to a volunteer librarian and receive a well-researched answer back within about a week.
IPL kids page
23 research steps for kids from ALA
Great Websites for Kids is a compilation of exemplary websites geared to children from birth to age 14. Suggested sites are evaluated by the Great Websites for Kids Committee using established selection criteria. The committee is made up of members of the Association for Library Service to Children, a division of the American Library Association.
Newly evaluated and accepted sites are added to the database three times a year. The committee also reviews all sites within the database twice a year to guarantee sites are still relevant, appropriate and accessible.