The period of adolescents is the time between childhood and adulthood, which means that at times the adolescent acts like an adult and other times acts as a child.  One of the reasons that communication with an adolescent is so difficult is that they are in a constant state of change.  They want to be "grown up," but their development does not allow them to be at that point yet.  As the child seeks their own independence, they begin to shut down their communications with their parents.  In order for the parent to stay "connected" with their child, it is going to be their job to find out where the child's "tree house" is.  What I mean is where does the child find safety, fulfillment and fun.  It can be found in a variety of activities, such as sports, computers, craft projects, or hobbies.  It is necessary for the parent to find out where this place is for their child.  If the parent fails to find out, then their child will drift farther and farther away.  The child will begin to involve themselves in activities that you do not approve of, but you will not know about them, because you are not in their "tree house."   

Children in this situation fall into the A, B, C, structure, which is attitude, behavior, and consequences.  A child left to himself will go down this undesirable road.  The first element, as you can see is "attitude."  The child will have a harsh attitude, which is meant to keep you away from them.  They want their own independence and because you have not availed yourself to make yourself a part of their lives, then they're going to seek to "lock the door," and keep you out.  Following their attitude shift is a change in the child's behavior.  They want to "hang" with their friends, stay out longer or stay in their rooms, where they cannot be monitored.  The final step is "consequences."  This stage is when the child receives consequences for their behavior following the first two stages.  This is a very serious stage which needs to be dealt with.  However, if you can catch the child during the first stage of "attitude," then it will be easier to inerrupt this cycle.

Please let me know any questions you might have related to this issue.  I'll be glad to help!

"No success in public life can compensate for failure in the home."

Benjamin Disraeli