There are family situations that require special considerations.  In the case of a divorce one parent may have full custody and the other although listed and with parental access is not to be contacted with regards to school decisions.  Unfortunately, there seems to be no way to make this information ready visible to teachers from the bulk mailing features or the Roster views in onCampus.

It would be my suggestion to use the "No Contact" feature on the contact card in conjunction with the comment/notes feature to be able to remove that persons email address/phone number from the onCampus Advisory, Team, Activity and Academic groups. This will help to avoid some very awkward and unpleasant conversations.