I have a feeling that five or ten years from now (after going to college) that some of the "boycotters" are going to regret what they did. It'll obviously be too late for Constance's (first) senior prom, but those people will feel much more urgency for doing the right thing... because they have first-hand experience of how sinister the wrong thing can be. Also, the attendence was probably dictated more by parents rather than children (even given there is a strong correlation of attitudes between them), so the numbers are going to be more representative of the parents in that area.
By trying to absolve himself of responsibility, the administrator left the population to their own devices, and the people in that area (generally) showed how bad people can be. Because of the visibility of the sequence on certain parts of the Internet, the major characters involved will not be able to run away from their past. And given the attitude trends regarding GLBs, history will not treat the boycotters (especially the vocal ones) kindly.
It just really sucks for Constance right now.