I've wanted this ability too -- but when I look over the Google Apps API, I don't see any method exposed to manage the settings for individual members of a group. And if the Google API doesn't have it, it can't really be added to GAM.
Here's an alternative I've been meaning to try (don't know if it will work!) -- add your faculty list as a member of the student group(s). Then set the delivery option for the faculty group (using the interface) to "delivery no mail". I hope that will do the trick. Hopefully in that situation you won't have to give all of your faculty members "post as group" privileges on the faculty group to make it work.
Good luck, and here's hope that Google adds those features to the Groups For Business API!