KidBlog is such an excellent platform allowing for a place for students to post their writing, pictures, or videos. With its settings you can make the postings public or just within your class or other classes using KidBlog.
This is the first year I'm doing the connections with other classes and kicking myself for never doing it before. All you need is the URL of another teacher (Let me know if you would like to join my class's) and to change a few settings.