History: RolePerms

Whenever you create a new Workspace Role, a new tiki group is created, named RolePerms-whatever-was-the-name-of-your-role
This group is where you have to assign permissions that you want your role will have on the workspace's objects.

So if you assign 'teacher' tiki_p_edit, he will be able to edit pages in the workspace, but not anywhere else.
This group doesn't need to be included in any other group.