Joey, I work with teens for a living. I don't know how old the kids you have are. I'll speak about teens, since that's where my experience is. You can adapt to different age groups as appropriate.
Teens may speak with confidence and bravado, but they are looking to adults to teach them how to be mature in the world. Whenever you speak to them, keep that foremost in your mind. It will help you to stay professional.
Gently and lovingly correct their behavior. For example:
Unruly teen: "You're a lesbo, aren't you?"
You: "First of all, you don't want to use that term. Some people would find it offensive. Second, it's something you don't want to ask someone straight out unless they're a close friend. It's personal. Third, you don't want to talk that way to an adult. They'll remember it. You don't know when you're going need someone on your side."
Unruly teen (maybe to one of his/her peers): "Jeez, what's eating HER today."
You: "I'm only telling you this because I like you. These are lessons you're going to need to learn. I'm on your side. Not everyone will be."
You get the idea? You're there to show them how to live their lives successfully. Whether or not they appreciate it, you're doing them a favor by correcting their brazen rudeness <<ahem>> I mean, by correcting their social faux pas.
I hope this helps.