Edshelf. This is a nice network for teachers to share and find resources such as lesson plans, videos, and more. Also, a teacher can use TeachQuest as a secure environment to collaborate w/ parents. Teachers can communicate via a blog, chat, forum, and more.
I highly recommend checking out TeachQuest by clicking here.
For my Pinterest board on Social Networks in Education click here.
For my Edshelf collection on Social Networks in Education click here.