You can add a relationship to both an organisation and a person when you are editing them. This relationship field can contain any number of values in a drop-down. So for example you could use it to display the strength of the relationship (‘strong’, ‘weak’) or temperature (‘hot’, ‘warm’, ‘cool’, ‘icy’) or the duration (‘<1yr’, ‘1-2 yrs’, ‘>2yrs’), or the value (‘0-10’, ‘11-50’, ‘51-100’, ‘’101+’) of a school. Use whatever values work for your organisation.
Only Super Users can add new Relationships, so if you can't find what you need in the list, please speak to your Super User.