I have a question. Does your brother want to go to college? Pot does kind of take the wind out of your sails as far as motivation goes. It is hard to get someone to stop just because you tell them to. It is viewed by the people smoking it as a mellow past-time and not hardcore like other drugs or even drinking. If he denies it, what will you/your parents do? Accept his answer or confront him more? If he admits it what will happen? Will anything change on the homefront? Will he be grounded/not allowed to see friends?