In each class I have taught I have found that I usually have at least 1 syudent who has an excuse for everything, or at least most things. The best way I have found to deal with these type of students is to give them encouragement while at the same time making sure they understand the class grading policy does not make exceptions. After the first week these students usually get on bored and stop with the excuses. Occasionally I will get a student who can not seem to get it together. This student is usally failing my class due to attendance issues, missing assignment issues, and participation issues. By mid term i end up having a very serious sit down discussion with this student and I find that not sugar coating the truth is most helpful for this kind of student. I lay out where they are at and where they are headed should they continue the course they are on. So far this seems to work really well.