5 Common Mistakes in Writing Lesson Plans
Want to contribute your own lesson plans? Make sure that they are well-written by using these simple guidelines.

Discovery School - Lesson Plans Best of the Net
DiscoverySchool gives access to 400+ free classroom-ready lesson plans and activities for K-12 education, organized by grade level and subject for science, social studies, and literature. Check out these awesome resources.

Encarta Lesson Bank
Encarta has put together a great site where teachers can access and add to their lesson plan bank. Many of the plans include further info using the encyclopedia.

The Gateway to Educational Materials
This is by far the easiest Lesson Plan data base to use. I have now used over 5 of the lessons for my American Government class!

Teachers.Net Lesson Plans
Teachers have submitted numerous lesson plans. This site is convenient because it is not only laid out by topic, but also by grade level and learning level.