Enable the event monitor [Site administration  ► Reports  ► Event monitoring rules] . Add some site level rules such as a course was updated. Go to the event monitoring page. User menu -> preferences -> Event monitoring. Check that the course selector has an option of 'Site' and that site level rules are available to subscribe to. Log in as a teacher and view the Event monitor page. Make sure that they can also see 'Site' in the course selector and that site level rules are available to subscribe to.