To protect children as they search the web we may choose to use search engines that have been programed to screen their young users from inappropriate content.

KidsClick - The search engine for kids created by librarians
Ask Jeeves for Kids - A natural language seach engine for children
Google - A search engine without racy banner ads4
OneKey - The kid safe search engine
Lycos SafetyNet - A filtered search for kids - free registration req.
Ah-ha.com - Displays sanitized results for your searches

These directories have been created for use by children.  Content is screened and the interfaces have been created with kids in mind.

Yahooligans  - The oldest and best directory for kids
Lycos Kids - Directory for Kids
Kidsites.net - A Directory for Kids
Super-Kids.com - Child and family friendly stuff

These resources have been screened categorized and sometimes rated and reviewed for use by students.  In many cases these sites also have assembled various resources to help students and parents with homework and research projects.

Searchopolis - K-12 search resource and homework help-site
Infoplease.com  - A kids almanac and homework hep site
Study Web - Quality Web resources to help kids with research
3datlas.com - An atlas online customized for kids
Bigchalk.com - The education network
Refdesk.com - A good source for fact finding on the Web
Awesome Library - Reviewed resources suitable for kids
Edview.com - Teacher - reviewed sites for kids