You'll love reading Wings: A Tale of Two Chickens to your preschooler. I did. A cute story and a lesson about the importance of reading.
Description: http://apod.nasa.gov/apod/ap101126.html
http://cs.gettysburg.edu:8080/jumpmaze/
A fun daily puzzle for your puzzling homeschooler
http://www.goodeveca.net/CFGoodeve/habakkuk.html
Amazing intersection of science and history.
Check out http://mathta.com for advanced math worksheets, including decimal places and Algebra
(or at least not flat)
Two views of the Orion Constellation one from the Northern Hemisphere, one from the Southern
The different orientations of Orion show the two viewers are upside-down with respect to each other