If you have never spoken with him before, the first thing you must do is introduce yourself. If he already knows you start a casual conversation about an after school activity, a hard teste you both had to take or about your interests. To keep the conversation going, ask him about himself. Most people like to talk about themselves. ( Not meant to sound egotistical.) Remember to be confident in yourself because it will really reflect when you talk to him. Just remember that talking to someone new isn't that scary and that you will do fine.