You can hide any specific lists, lessons or assessments to prevent your students from seeing work that you are not ready for them to have access to. This can be beneficial for students that tend to jump too far ahead without focusing on their current work or for preventing students from seeing an assessment before they sit it.
Make sure that you are in Edit Mode of the Content Browser by clicking the Edit button at the top right.
Click on the content you are wanting to hide in the Content Library. This will bring up a sidebar to the right of the page containing the options available for the content you have selected. Text shows which people can currently see the selected activity; either teachers only or students and teachers.
All teachers in your school can always see all content, regardless of visibility settings.
To change the activity's visibility, click on the eye icon (as seen below).
Once clicked, the eye icon will change to have a line through it, and a green eye icon with a line through it will appear on the list itself (example seen below), this means that the content is now hidden.
To unhide an activity, just click the eye again.