Cascades Volcano Observatory - comprehensive volcano information.
EarthEd - links to earth science education resources.
Earth Sciences Resources: WWW Virtual Library - links on all aspects of earth science.
Earth Science Topics: Yahoo - a list of the earth science links available through Yahoo.
Electronic Volcano - maps, photographs and descriptions of active volcanoes worldwide.
The Gateway to Astronaut Photography of Earth - view photos of the earth taken from the Space Shuttle; view a particular feature or area of the earth.
Geology Gems - Winona University's earth science program. Also offers pictures, links, and stories.
GeoScience: K-12 Resources - an amazing list of earth science resources.
Google Earth - Google's free and premium software that lets you virtually fly across the landscape of the surface of the earth.
Google Maps - Zoom in and view the landscape across the world.
Integrated Earth Information Server - access to real-time environmental observations: weather maps, oceanographic, seismic and other environmental information; made by observing systems around the globe and delivered to the IEIS by the Unidata Internet Data Distribution (IDD) network.
Michigan Technological University Volcanoes Page - a great source of scientific and educational information about volcanoes.
The Mineral Gallery - comprehensive descriptions and images of minerals.
Minerals and Metals - this page, produced by Natural Resources Canada, provides pictures and information about the minerals and metals of Canada, and the communities associated with their production.
MSN Virtual Earth - MicroSoft's earth viewing software.
Perry-Castaneda Library Map Collection - extensive collection of maps covering every area of the world.
Rocks and Minerals - an index to everything mineralogical.
The Virtual Earth - mentions many good sources of earth science reference material.
Volcano World - links to pictures, recent eruptions, a Hawaiian tour, and how to be a volcanologist.
Wikipedia: Earth Sciences Portal - collaborative portal covering earth science.
Yahooligans: Geology - Geology links and resources.