A blog is a great tool for the classroom and there are many great ways of using them!
If you are thinking about the English content area, blogging can improve your students' writing skills. They can help build confidence in writing and give your students a voice. I would love to use blogging as an extra component in writing because it is more creative and can spark students interested in writing when they may otherwise not be interested.
Unlike other writing platforms, I think blogs are great at organizing student work. This makes it easier for the teacher and the student. I know I would have loved that aspect of having all of my work in one place as a student.
For my classroom, I would love to have one blog that is for the whole class, much like some of the ones I found in my last post. I would link videos and articles that are relevant to the students and give them additional web sources and tools that could help them if they are struggling with homework. But I also love that they then could have their own blog. I think they would take their work seriously if they knew it is being published to the world. It teaches them great skills that they need to know later in life.