if you decide that you can only put an end to thisjunk by getting in a fight, then let him throw the first punch. if he hits you or your friend, then tell him not to do it again. if he does it again, step in between him and your friend, and tell him this is his last chance. if he does it again, let him have it. in most schools, and areas you wouldnt get in any trouble if you try it this way. he started it, and you gave him plenty of warning.
Even if your father will back you up you could very easily end up charged with third degree assault.
well if he decides to play that way, you could charge him with harassment.