The student will join one of two newly created special interest groups representing each of the remaining two priorities. And then there were two. Now those of you in the groups left out in the cold have a decision to make. You've got to join one or the other of the two remaining.
Students negotiate the nature of the new groups and the issues they represent.
The class polarizes into two distinct factions. They select spokespersons for their respective sides. This is where things can get unwieldy if you aren't careful. Consider the smoothness with which they cooperate. The media will, of course, call any rough spots to everyone's attention.