Many things about Blogger make it a popular choice for middle school and high school classroom blogs. It's easy to create a blog on Blogger, all back end maintenance is done for you by Google, and if your school uses Google Apps for Education it can be added to the list of services your students can access with their Google Apps for Education accounts. There is one thing that can't be done easily and that is moderate students' posts (not comments, posts) before they go live on your classroom blog. But if you have students post via email then you can moderate the posts before they go live.
The screenshots below provide directions for enabling posting via email. When you get to the third step select "save as draft" as the default setting. That setting will require you to manually approve posts from your Blogger dashboard before they go live on your classroom blog.
Step 1: After signing into your Blogger account select settings from the drop-down menu next to the name of your blog.
Step 2: Select "mobile and email" in the settings menu.
Step 3: Specify the secret email address to which posts will be sent. Select "save as draft" if you want to moderate posts before they appear on your blog.