I’ve used blogs over the last few years with friends to follow travels/lives. In schools, blogs are now being used by teachers to show what they’re doing in class, post homework assignments, test dates, etc. I find this very useful, especially when students are absent and need to get caught up. This works well when the student has access to the internet at home.
I follow the blogs of several of my colleagues in my department from other buildings to compare what we’re teaching and stay on the same pace. It’s helpful to see what they are doing from day to day, especially when we’re teaching the same classes.