Laughter

There are times when I just can't help but laugh at my students (maybe I should say "with" but it really is more laughing AT!) Today, in Bible class, we were going over a worksheet. Here's how it went.
We were well into the class and, amazingly enough, they were fairly well behaved with very little talking (this is my class of 5 girls and the rest of them are boys!). I was moving quickly and everyone seemed to be paying attention.

Me: Matt, number 5. What did Jesus say to the man in this story?
Matt: I'm coming to your house.
Me: John, number 6. What did the man do?
John: Um...I have a question.
Me: Answer the question, please, and then you can ask your question.
John: Climbs down and goes to his house.
Me: Okay. Now, what is the question?
John: Um...Does anyone else smell Chinese food? Cause I do. It's making me really hungry!
Me: (Looks at John, not quite sure how to respond)
Andrew: (from across the room) I don't smell Chinese but it smells like Mexican over here.

How do I keep from laughing? Random!!