Advise on how to handle young neighbors and off leash dog

but don't sneak off quietly into the night and do it.

call animal control. they'll come pick up the dog - maybe the owners will see, and realize what they are doing.

Animal control cannot seize a dog unless it's clearly been starved/abused. All they will do is fine the owners for off-leash. If they pick up a loose collarless pit bull they will almost certainly end up killing it.

umm... no - animal control has the right to take any dog that is not following the rules/codes. Animals roaming at large are not in code - therefore responsibility of animal control. Animals have to be held for a minimum number of days to allow the owners to claim the dog.

No owner present, means the dog is a stray, and the responsibility of the local animal control.

no - animal control has the right to take any dog that is not following the rules/codes.

where do you live? most places it's practically impossible to get AC to take a clearly owned animal. The animal has to be documented to be a severe abuse case. Stray ID-less dogs go to the pound and three days later most are put to death. Asking AC to take this poor dog (which they won't just because it's violating leash laws) won't be doing it any favors. They won't put it up for adoption.