Very yucky indeed and not for the weak of stomach. Athena Earth and Space Science for K-12 has lessons and curricula dealing with several different areas of science. PBS' Nova Online deals with numerous science topics. The Discovery Channel's Web site has lots of interesting articles and activities for students and teachers. There are archives of questions, links and more.
Files has interesting news and archived articles about different issues and topics in science.
The Science Learning Network. The always cool Bill Nye the Science Guy. Good general science resource site that has articles, experiments and more.