Can I leave for Thanksgiving early?

I will be gone to NCA the Thursday and Monday before Thanksgiving. An interesting issue has arisen in my organizational communication class. Originally, I had scheduled an activity for Thursday that could be led by someone else and a work day for Monday to give them time to work on their group projects. This week, a student asked me what we'd be doing on that Thursday. When I said I was still thinking about it, she said, "could you decide quickly? It affects travel plans." These students have griped all semester about how they have so little time in class to work on their group projects (and they're all too overcommitted to find time outside of class). This was one of the few times in my teaching experience thus far where I actually had to hold myself back. We are not allowed to "cancel" class, so I have often allowed groups to work on their own and email me a report of what they did as a way of checking attendance. However, I think that I will require them to be in the classroom for both days and have someone come to the class to take attendance. Of all the nerve...