HotBot very large web index Go - Ranks web pages. Magellan - Searches for ideas and concepts, not just key words. Rating system for minors. Guides are assembled by librarians or proven experts in the subject. LookSmart - A directory similar to Yahoo.
Subject directories are easy to use.
Snap - Another large directory. Features easy to use subject directories and other easy to use resources. Authors of web pages must submit their pages to be included. Google - A popular search engine with educators. There are not distracting advertisements.