If you were selling Girl Scout cookies, this would not be your problem. You would report the matter to your local Girl Scout Council, which would report it to Girl Scouts USA, which in turn has processes in place to get the money.
Was the selling of nuts and chocolates authorized by your local council? If so, turn the problem over to them. Even if not, see if they can help.
If not, you may be out of luck. You could say: If you can't pay, please give us back the unopened boxes. You could also toss the girl out of the troop, although that's not a nice thing to contemplate.
You could say: When will you have the money, and in cash? See if maybe you get an honest answer. If that doesn't happen, it's clear that the mother has no intention to pay.
Was this a matter of a few boxes purchased by the family for their own use and then found they didn't have the money to pay? Or was it a large order, where the girl collected the money from the people who wanted the product? If that's the case, the family likely pocketed the cash and then wrote you a rubber check...bad stuff.
Forget about criminal charges. It is more of a civil matter, but it would cost money to bring the civil case to court.
At any rate, hopefully I've given you a few things to think about. Good luck!
$172, huh? Yes, that's a large amount. For the future, you probably want to follow the GS policy regarding cookie sales even when selling other items: they don't accept checks from a single individual for more than $100, which limits their losses in such instances.