This pattern of behavior might suggest your son could be using drugs. I know it sounds offensive to you, but if a dear friend of mine had heeded the early warning signs she might not have had all the heartache. I am especially alarmed at your son's need to sleep that long and the anger that goes along with it. Every parent with a child who has experimented with drugs would love to be proven wrong. My friend was in a constant state of denial, even after her son was caught at school with drugs. He assured her it was the first time he had tried it and she believed him. He took drug counseling but the parents found evidence he was still using. He says he is no longer doing drugs. His behavior during this time was that of your son's. I'm not saying your son probably is using drugs, I'm just saying it's something to be wary of - for your sake and his.
Dear Monica,
Teenagers can behave in this manner for a variety of reasons. Your son may display a mood disorder; he may display what is called a conduct disorder - i.e., a serious personality disorder; he may have some learning disorder, now culminating in school refusal after years of struggling with school and developing a negative perception of school.
Whatever the reason(s) for the behavior, he is in need of help. One course to pursue is an evaluation by a mental health clinician, who can help you and him make sense of the situation and plan accordingly.
Another course, depending on where you live, is to approach the local court for assistance via what, in many jurisdictions, is called a Child In Need Of Services (CHINS) petition. This process is designed to address truancy by building in services and allowing the court to underscore the necessity to attend school and to support your authority in this regard.
Another course is to approach the school district and request an evaluation of the need for special services, in light of your son's response to school.
Whatever you do, put some of your energy into seeking help. Otherwise, you may likely go on battling with your son indefinitely, with no gain.