DiscoverySchool
Kathy Schrock's guide for educators is an excellent site, regularly updated to include the best sites for learning and teaching. Categorised list of sites useful for enhancing curriculum and professional growth.

Edsitement
Resources for teaching English, history, art and foreign languages. From the National Endowment for the Humanities.

Education Index
Education Index is an annotated guide to the best education-related sites on the Web. They're sorted by subject and lifestage, so you can find what you're looking for quickly and easily.

Education World
A huge range of reference resources, classified by subject, for educators.

Fom Now On
Jamie McKenzie's Education Technology Journal provides current news and information about the learning environment. Subscription is free.

The Global Schoolhouse
Collaborative venture with Lightspan.com. Brings together resources for teachers to communicate and share learning experiences. Links to collaborative projects, communication tools and professional development.

Landmarks for Schools
Developed by the Landmark Project, this site is dedicated to the idea that information is the raw material with which students learn to build. Excellent resources in sciences and social studies, links to other sites for current awareness news and web tools.

National grid for learning
An initiative of the UK education department.

New horizons for learning.
A cleverly designed site structured like a building with different levels for locating information.

TCRecord.org - The voice of scholarship in education
A site with regular thought-provoking , but scholarly, articles on a broad range of issues in education. Registration is free.