I suppose it would depend on the prank, but I imagine I'd come down hard on the idea of vandalism as harmless fun. I'd assure him that he'd be repairing or replacing anything that he and his friends damaged, and I'd be sure to alert his friends' parents. I might also give him an idea of what it costs to restore the paint job on an egged car.
"This is a great opportunity to build trust with your teen and really confront an issue head-on," says clinical psychologist Jennifer Powell-Lunder, co-author of "Teenage as a Second Language: A Parent's Guide to Becoming Bilingual" (Adams Media).
Open an honest dialogue with your son and ask him to step in with some honest answers of his own.
"Sit him down and say, 'Look, I know you have this plan, and I'm sitting here grappling with what I should do. Part of me says we should talk this through and you'll reassure me that you're not going to go through with this prank. The other part of me is saying I need to keep you home to prevent you from doing something that you might not think is a stupid thing to do, but I know that it is.'"
She suggests asking your son what he thinks you should do.
"You're doing this to secure his commitment," she says. "This is a teenager. You've expressed your concern and let him know you're not OK with it, but you also need to have a talk that reflects his independence."
You also have to be prepared for his answer.
"Nine times out of 10, the kid is going to say, 'Fine. I'm not going to do it,'" Powell-Lunder says. "And you tell him, 'OK, but you need to know I'm going to be monitoring the situation and I'm going to check up on you, and this is an opportunity for you to prove yourself and rebuild my trust."
"He could say, 'We're doing it anyway. All my friends are doing it, and none of their parents have an issue with it,'" Powell-Lunder says. "In which case you say, 'I'm your parent, and if you're honestly sitting here saying you're going to disregard my word, you're telling me you need to stay home. And that's what you'll do.'
"It's possible your kid feels so peer-pressured to participate that you're actually giving them an out by keeping them home," she adds. "Or it could just be bold defiance, in which case you need to let them know that won't fly. Either way, our role as parents is to set limits."