1. Click Turn editing on at the top right of your course page:
2. Click Edit settings to the right of the activity you want to restrict access to:
or
Click Edit topic to the right of the section you want to restrict access to:
3. Under the Restrict access heading, click Add restriction.
4. Then click on the Group button.
5. Select the group that you want to restrict from accessing the assignment/section from the drop down menu.
6. You can shut off the eye if you want other students who are not in this group to see the warning: "Not available unless..."
7. Save changes.
» Guide to Moodle