As the teacher of your class, you have control over what is posted to and commented on in your Kidblog class. You also can provide a private comment to a student in your class.
How to video: Setting privacy levels
Step-by-step: Setting privacy levels
1) To manage the privacy settings of your class, go to Settings -> Privacy (class Privacy page).
2) Select which audience students are allowed to publish work for, as well as, if their work will need approval prior to being published for that particular audience.
3) If you are allowing comments, scroll down on the page and you will be able to set who is allowed to comment on your students' posts.
Teachers are able to send "Private" comments to the author of the post. Simply check the small box labeled "Private" in the bottom right-hand corner of the comment.
Only the teacher and the author of the post will be able to see this private comment.