My class policy is "no late assignments", for any reason. I find that this is more fair to everyone then trying to decide which excuse merits exceptions. My students know that they can fax, email or have another student hand in their work, but if I don't have it by the beginning of class, it won't be accepted. My grades are also weighted so that missing one assignment won't have a huge affect on the student's grade, but multiple missed assignments will.
