It's always a flag when you're happy if a student happens to be absent, but what a relief to be able to teach your class without the distractions that certain kids regularly create. Such a situation illustrates the struggle that teachers face to balance the good of the group against the good of the individual.
As contrary as it might sound, I generally appreciate the disruptive student because she will not allow me to ignore her, and by so doing to fail her. She is usually not the only student who is unengaged by my class or lesson, and she does me the courtesy of letting me know. Even so, in the midst of working through all the issues involved, it's hard not to get frustrated and a be little resentful at times-- after all, not many of us became teachers in order to deal with contrary children. But many of us did become teachers to make a difference by reaching kids, and it's silly to think it should be easy.