the great thing about our society is:
they are minors,there is not a damn thing you can do to them
they know this
if you touch,threaten or harm them, you go to jail and they win again
nothing you can do will bother them
the worst that will happen is the cops are called, they smack them on the hand and for the nexe 6 months to a year they have weekly visits with a probation officer. maybe a week or 2 of juvenile hall, but doubtful life sucks been through it. trust me there has been hundreds of times i wanted to knock my step daughter's head off but she would have just called the law and I would have been the bad guy and in jail.
I feel terrible about your car but there is really not a whole lot you can do about but lick the wounds and fix it.
I worry everyday that this is going to happen to one of my cars, just been lucky so far. they would probably burn mine to a crisp.