Yes it was done before. The only difference is, you're right, the teens would have been shot or strung up. And such punishment would have had some sort of deterrent effect.
The boys in question today will get free legal help, paid for by our tax dollars, and their grieving, welfare-besotted, fat overweight mothers will sob on the stand that they are good boys who just got a little wild.
Every time you think that it didn't happen before, read the first five books of the old testament.
"How has our society crumbled so completely? HOW? THis was not done years ago! IF it was, the teens would havebeen shot!
1) Progressive Education.
2) Emphasizing rights without responsibility to 'children'.
3) Delayed justice.
4) Drugs instead of the healthy fear of ass whoopings(in school & out).
5) Ending moral training, as in, removing the bible from the classroom, which gradually removed the fear of God societally(pretty much permanently at present).
6) Sex education(supported by #2).
And it will happen again. Apparently this is not an isolated incident at that school.