Need help nabbing these vandals ... pls advice !!

Good to see the wheels turning in the proper direction.

Since they are 16 y.o ( 2 of them ) it wasn't made public , I hope they go to jail for few nights.

Publicizing their names is one thing, publicizing their crime and it's having consequences is another.
The ignorant need to be educated, making a "public" example out of these clowns is a good way to do that and prevent future victims of ignorant behavior.
I'd suggest approaching the local news organizations about running the story.