My approach, right off the bat, every time:
1. They're not in trouble, not with me.
2. What can we do that they like? Something we can talk about? Something we can talk about? I played Jenga during an amazing session with a freshman last week. His favorite game, because he loves the crash... which gave me another snippet into something he likes.
3. "My main purpose here is to hear what you have to say." Most kids love that. Teen kids. Little kidlets. Because when they start going off, it's "EXCUSE ME?! We do NOT talk like that in here, mister!! Say it again and it is ISS FOR YOU!!!" Of course they're going to say it again. I've had students tell me that their ex-best friend is a stupid b**** c*** wh*** and they hope they fall off a bridge, and I just remain unphased. "Why do you feel like that?" Let them go off and just remain cool and collected, and they'll start calming down. Mix in some Jenga or let them draw or talk about sports if they're into that...
... my bad. You didn't ask for all this.
What do you do? You said you're working with a 9th grader. Are you in the mental health field?