step son

my step son is 14 years old, he's living with me and his dad and goes to his mother on weekends. for the last 6 months, his father is not home all day, he started behaving in a very rude and aggressive way, he does not follow my instructions and he's deteriorating in everything. he's always trying to provoke me, so we decided to change the situation and let him stay with his mother and visits us on weekends. he's trying to break this new situation and when his father told he has to follow the rules he took all his stuff and started destroying the walls in the room, his bathroom and anything that belongs to me or his father in his room; our cds, ipod, magazines,,,
what can we do? is it an anger crisis or just he's not behaving?

[mammo]

I think he has a real anger issue going on, probably over the divorce.  He needs to see a specialist to help him deal with his feelings and resolve them.  This may mean all of you being involved in his therapy.  I would address this right away before his anger worsens, and to get him back to a normal, happy teenager.  Good luck and take care....