Blogs in Education is designed to provide some resources if you want to get started or expand using blogs for yourself or with your students. The site is done by the University of Houston. From what I can tell, they link to many of the good/useful sites I've run across.
The use of blogs in instructional settings is limited only by your imagination. Here are some suggestions from this site.
Options for instructors using blogs:
Content-related blog as professional practice
Networking and personal knowledge sharing
Instructional tips for students
Course announcements and readings
Annotated links
Knowledge management
Options for students using blogs in your courses include:
Reflective or writing journals
Knowledge management
Assignment submission and review
Dialogue for groupwork
E-portfolios
Share course-related resources
I'd really like to know about other sites or what you think of this one. Share!