I spoke at the Vermont Library Association Conference a couple years back and at that time was developing a science reference website for K-8.  The site has just received the American Library Association inclusion in their 2008 Great Web Sites for Kids.
I hoped librarians in Vermont might share it with their teachers and students if it is helpful. It’s called the Exploring Nature Educational Resource.  http://www.
I hope you find it useful for a science supplement.
Best wishes,
Sheri Amsel
Exploring Nature Educational Resource