Links to Unit Studies approach to homeschooling:

An article on Unit Studies:

http://www.unitstudy.com/articles/unit_study_101.htm

Definition taken from the above site:

What is a unit study?
It is defined as an in-depth study of a topic (space, trees, cars, etc.) that takes into account many areas of the topic, such as geography, science, history, art, etc. It is a complete immersion into the topic so that the student will see things as a “whole” instead of bits and pieces learned throughout their education.”

Resources:

Unit Studies you can purchase, has a long list of categories and provides an overview of what it contains.

http://www.unitstudy.com/index.htm

FREE Printable Unit Studies:

http://happyhomeschool.familyclassroom.net/Archives.shtml