Don't cut schedules too close, especially if transportation to and from the airport has to be reserved. Granted, some college class schedules don't leave much time before the last class/exam and a holiday but your student needs to consider the possibility of a late ending class or last minute errands or even finishing up a term paper a few hours late. Planning the return to campus a day early to allow for flight delays is not a bad idea.

Thanksgiving is a tough time for getting good fares. If the class schedule is known, keeping trying the airline web sites starting the afternoon of the 332'nd day in advance may be the best way. It may be worthwhile for your student to not come home for Thanksgiving if all the cheap seats are gone.

Travel tips:
http://members.aol.com/ajaynejr/travel.htm