How can I block students from creating accounts?
Step 1: Go to your name menu at the top and select the "Admin" link.

Step 2: Under "Settings", uncheck the box "Allow students to create/edit their own user accounts".
Note: With this setting unchecked, students must be added by an administrator using the "bulk upload" or "add single student" option, or through a SSO service such as Classlink or Clever.
