The teenage brain is still developing. While teens might seem like younger versions of adults, having the same abilities for rational thought and empathy that their parents might have, they don't. The frontal lobe, which controls things like emotions, behavior control and decision-making, isn't fully developed until an individual is in his early 20s, notes the National Institute of Mental Health. Combine a not-fully-developed brain with the fact that the teen years are also a time of self-discovery, as well as testing boundaries, and what you often get is rude behavior. While the bad behavior will likely change as your teenager matures, it doesn't mean that you should ignore it or let it slide.
Remain calm. Answering rudeness with rudeness will only escalate matters. Instead, the University of New Mexico Cooperative Extension advises that you should say something like "I'm sorry you feel that way, and I'm glad to listen to your opinion, but we don't speak to each other in that manner in this house. Please rephrase your comments."
Postpone the conversation until a later time if you find yourself feeling too angry to talk calmly. Tell your teen that the way she is speaking to you is upsetting you and you need some time to calm down. Explain that she can use this time to consider her actions before you finish your talk.
Set boundaries for appropriate behavior if rudeness becomes a consistent problem, advises the Raising Children Network website. If your teenager knows that it's inappropriate for him to say certain things to you and he says them anyway, he might just be testing the boundaries you set up. Discuss appropriate consequences for this rude behavior. This lets your teenager know what to expect if he breaks the rules.
Consider the comment before acting. You need to determine if your teen's comment was truly rude or hurtful and aimed at you, or if it was something said in passing and wasn't meant as disrespectful. If there was no intent and your teen is otherwise behaving well it might be best to just let the comment go.
Enforce the consequences if you decide that your teen's comment was intentionally rude. When you follow through with the consequence, your teen might think twice about being rude the next time. According to Education.com, you shouldn't argue with your teen nor make deals about the consequences. Just say, "I cannot tolerate this rude behavior and this is the consequence to which we both agreed."