This blog has great links to citizenship-related exercises and teacher resources, such as the US Constitution in simple English. Should be an important resource for US teachers of adult ed, as well as teachers of American culture overseas.
This is an amazing resource for teaching high school/adult ed. It is video-based and free--individual students can sign in, or a teacher can register a whole class and keep records of their activities. There is an excellent explanatory video for teachers also. Lots of listening/speaking/reading practice.
This is a totally cool way to look at Flashcards, and includes not only polls taken by Webheads, but some lesson plans for use with your students. (Note also the way the blog entry is organized.) Study and blog by Karenne Sylvester, Webhead.