free homeschool resource (free textbooks and courses)

This is an awesome free resource that includes free digital textbooks and courses in various subjects. There are physical science textbooks, algebra textbooks, courses on music appreciation and music theory, just to name a few.

http://cnx.org/

A complete astronomy course for high school, along with some physics and Earth science and a upper level math thrown in.

http://www-spof.gsfc.nasa.gov/stargaze/edufiles.htm