The Howard Hughes Medical Institute has a wonderful resource for science educators called Cool Science. Cool Science is essentially a collection of HHMI resources:

• Ask A Scientist interface for answering student questions about science. This site connects you with some top scientists from around the country.
• Cool Science for Curious Kids has 5 interactive biology activities for young scientists
• Becoming a Scientist has videos from biomedical researchers describing the qualities necessary for a successful science career
• Biointeractive features videos, interactives, lectures, virtual labs, and more to support high school and college learners of life science concepts.

Applications for Science Teachers: This site is really 6 sites in one. Teachers of life science at all levels will find some helpful resources here. A definite must add to your bookmarks.