Blocking Blogs etc.

I am currently not teaching. I do not know if the school I was teaching at previously blocked blogs because I that time I had no idea what a blog was. I do know that they blocked social sites because memos were sent out about the issue. I do not know if a school would lift a blog for a specific class or not. It would be a great opportunity for the students, but it could be risky for the teacher. The teacher would have to be responsible for whatever their students blog about. There has been issues with texting and it could easily happen with blogging. Is there a way to avoid that kind of situation when blogging?