Science: 

Space Websites:

http://outreach.atnf.csiro.au/education/senior/astrophysics/stellarevolution_mainsequence.html

http://www.rigb.org/contentControl?action=displayContent&id=00000001107

http://www.nasa.gov/mov/196759main_049_LifeCycle_Star.mov

http://library.thinkquest.org/05aug/00108/homepage.htm 

Human Body Websites

Interactive heart diagram

The Virtual Heart

Heart Facts:  http://www.pbs.org/wgbh/nova/heart/heartfacts.html

Virtual Body

Cells Alive website - interactive cell diagrams

http://www.cyh.com/HealthTopics/HealthTopicDetailsKids.aspx?p=335&np=152&id=2402

http://kids.jdrf.org/index.cfm?fuseaction=home.viewpage&page_id=4B312651-5004-D739-A52F211666036011

http://www.factmonster.com/ipka/A0774536.html

http://kidshealth.org/kid/htbw/
http://www.innerbody.com/

http://kidshealth.org/parent/medical/body_basics/immune.html

http://www.kidskonnect.com/subject-index/31-health/337-human-body.html

http://www.edheads.org/activities/knee/