Michael Linsin has an interesting post on how to handle disrespectful students. As he notes, "One of the biggest classroom management mistakes teachers make is that they take disrespectful behavior personally."
I have to admit I struggle with this sometimes myself. The key as he says is to simply follow your class policies and enforce whatever consequences you have pre-determined and to do so calmly and dispassionately. He goes on to say:
Enforcing your classroom rules—which should include a rule specifically for disrespectful behavior—with an attitude of indifference strengthens your authority and your classroom management effectiveness.
This can be a challenge at times because initially, as a jolt of adrenaline surges through your body, it can make you feel like somehow the student won, that he or she got away without knowing how their disrespect made you feel. But a student only wins when they’re able to get under your skin...Rest assured, you’re not folding or giving in by resisting the urge to react emotionally. Rather, your constraint is a model for your students for how to handle negative situations with poise and without lowering yourself to the same level of disrespect.
You can read his entire post here