Schoolwide group permissions allow you to designate a group role for the school's homepage to any teacher or administrator. This functions similarly to administrative permissions (see more about this here), except it does not give the user access to every group in the school Instead, customizing the group page, adding events, and sending announcements are restricted to only the schoolwide group.
To assign a schoolwide group level role to a staff member, you have to go to the Classroom/Groups page under the Administration menu. This will bring you to the Setup Groups page.
From the Setup Groups page, you can see a list of all classrooms and groups in the left sidebar. Click on the name of your school and click the “+” icon under either School Leader or Additional Staff to add a staff member to the group.
From the panel that pops up from the right, you can select any user in the school to add to the schoolwide group. Click on the plus sign next to their name to add them. You can select a role for School Leader or Additional Staff members from the dropdown menu next to their name. As soon as you save the group, that user will have all the Group level permissions associated with that role. The default role is Group Leader. 