I have just joined a ning...called curriculum 21
This was minutes after I learned what a ning is!
I think it's a bit like a wiki, a collaborative website with other added extras.
Anyway, I joined the ning and then made a group for teachers with children aged 5-11.
I was thrilled only one day later when 2 new members joined. Silvia Tolisano was one of the new members, author of langwitches blog.
Here's a very comprehensice slideshow about how to blog in the classroom. It's taken from her Langwitches wiki