This can be a list of links to stuff that might be useful...
Full text - not just an ad or review.
The Underground History of American Education
by John Taylor Gatto
Our official assumptions about the nature of modern childhood are dead wrong. Children allowed to take responsibility and given a serious part in the larger world are always superior to those merely permitted to play and be passive. At the age of twelve, Admiral Farragut got his first command. I was in fifth grade when I learned of this. Had Farragut gone to my school he would have been in seventh.
All about teeth. Has a section on School Activities for Learning about Teeth and Gums, teaching materials and more. Whole book, free.
A History of Electricity and Electronics
Maybe not for the younger ones... bit boring for them. "The book requires no prior knowledge of technology. It is ideally suited to gain an understanding of electronics, for adults and young adults alike. Following the very human (and often quirky) discoverers and inventors makes the reading fun."
The Baldwin Online Children's Project
492 Classic Children's books online
This website provides a large number of free e-books, mainly about holistic agriculture, holistic health and self-sufficient homestead living.
Lesson plans, unit studies, software downloads, and activity pages. Loads more and a mailing list "full of homeschool freebies, great educational websites, and motivating articles".
Access to full course material from a growing number of schools and universities. Needs iTunes (free download).
MIT recently finished putting all their courses online. Highlights for High School might be of particular interest.
an essay; part of the Wildwood Survival website.
Anatomy diagrams and explanations, the rest of that science and nature site is worth a look too.
related to the spine, how it works, for children to learn from.
Campaign for a Commercial-Free Childhood
This is a page of links to their factsheets and a booklet about the ways in which 'marketing' is foisted on kids. Includes techniques, the commecialization of play, Food Marketing and Childhood Obesity, marketing sex and violence and loads more.