Step son

Ok here I go...I like to see if anyone can help me here...  I have a 15 year old step son who was in advance classes when  he was younger, and he is very computer literate and very intelligent.  The only problems are: he will not do homework at all....   he will do good on exams, but fails the rest of the classes... he is a social butterfly..    Also he is very disrespectful...I mean very! Examples: my hubby and I do not allow the kids to eat in their room...but he sneaks it in there...  If there is like chips ect. for lunch supplies...  like big bags.. he will have them eatten in a couple of days... so the youngest two may not get any because we dont know we are out...  which he doesnt take a lunch ( he chooses)   ...  He has a bad attitude with me and his father..by if he gets mad ...then the whole house is irritable..  by him throwing stuff...slamming things down...yelling ect..   He lies...  he goes into me and my hubby's bedroom and gets what he wants ..when he wants it..without asking....  he stills cigarettes constantly...which now I have to hide them when I do not have them with me...  my hubby put some expensive cologne in my underwear drawer because he didnt want him getting it... guess what...he went into my personal stuff to get it...   He will not go to sleep at night... my hubby has to fight with him until 2 or 3 in the morning...    btw...his mother has bipolar...so we think he has some of that..   the only thing I can say he does for hisself is wash his own clothes...Thats It!    He does not have any other chores... which hubby says since the kids are in school...he will take care of their chores...so they only have to worry about school...and when they are out...they can have a break!  WRONG!   My son which is the youngest...has chores...    All the oldest one does is play computer games, goes skate boarding, ect...  he does not have any chores!  Also since me and hubby got married...  the oldest will never leave the house..  the other two will go to grandparents ect...   but the oldest one does not go anywhere....  we even asked him if he will give us a weekend to ourselves... his story is.... well im in the room... i dont bother you...  we tell him thats not the point...we just want time to spend together...  does he do it?? NO!     He thinks he knows it all...which I know is normal teenage ****, but he can be a complete Butt!    Im sick and tired of him being disrespectful to me...  so any advice????

[remar]

I think you and your husband need to work together on this. Why should your son have chores and you husbands son does'nt? Start taking things away like his computer games and scate board if he does'nt listen. Kids need rules and structure.
He might be having a hard time with his Dad remarrying. Does he have any one on one time with his Dad?
Maybe counseling would help.