Tons of physics animations and tutorials, text, formula help. Explanations too!
http://www.glenbrook.k12.il.us/gbssci/phys/mmedia

NASA Interactive
http://pds.jpl.nasa.gov/planets/welcome.htm

Educational Materials on the Solar System
http://www.thegateway.org/browse/makesearch?past=keywords%7CNASA%7C%7C
yes%7CNASA%7C*keywords%7CPlanets%7C%7Cyes%7CPlanets%7C*

Animation of inner planets' revolutions
http://www.ac.wwu.edu/~stephan/Astronomy/planets.html

General Planet Site for Kids
http://www.planetpals.com/planetsize.html

Info on each planet with its own page
http://www.solstation.com/stars/4planets.htm

Current, up to the second representation of each planet's location
http://www.fourmilab.ch/cgi-bin/uncgi/Solar/action?sys=-Si

Homefires for homeschooling at 
www.Homefires.com

Carschooling with ideas and activities to teach every subject (including science!) while in the car, on the road 
www.carschooling.com

Awesome tutorial on poetry

http://www.mrs.umn.edu/cs/metrics/

Homeschool science supply company - free newsletter and instruction

http://www.hometrainingtools.com/catalog/cat_general-science.html

CIA World Factbook Every fact you ever wanted to know about every country. http://www.cia.gov/cia/publications/factbook/

http://www.extremescience.com/

General kid's science site:

http://www.madsci.org/

Women in science- great site!

http://www.astr.ua.edu/4000WS/4000WS.html

Amazing tutorial, Universe down to microscopic view:

http://micro.magnet.fsu.edu/primer/java/scienceopticsu/powersof10/index.html

This is a fractions interactive:

http://www.mste.uiuc.edu/courses/ci399su01/students/lenstra/final_project/fraction_students.html

Chemistry Lab Simulations:

http://www.dartmouth.edu/~chemlab/info/resources/applets.html

Beautiful Interactive Periodic Table

http://www.chemsoc.org/viselements/pages/pertable_fla.htm

Free worksheets, cheap books Dover- http://www.doverpublications.com/nc0035/

You've Gotta Geo-cache! http://www.geocaching.com

Aerial views of anywhere in the USA http://terraserver-usa.com/

Gardening site http://www.gardenersnet.com/

Learning Stream Curric. http://www.myaffiliateprogram.com/u/learning/t.asp?id=1178

http://www.welltrainedmind.com

Science site for homeschool- http://www.theyoungscientistsclub.com/

http://www.teach-at-home.com/

Cheap and used computers- http://dmoz.org/Computers/Hardware/Used/

http://www.saxonmath.com

Very inexpensive tapes of old radio shows- http://www.radio-showcase.com/

Math placement tests (free):  http://www.saxonmath.com/placement_tests.htm

Cheap books!!  http://www.bookcloseouts.com

 http://www.pearsonlearning.com/index.cfm?m=M1

Logic, debate, critical thinking-  http://www2.sjsu.edu/depts/itl/graphics/main.html

IQ test free-   http://www.emode.com/tests/uiq/

Cool field trip site http://www.virtual-field-trips.com/