It's circle time! O...K...
Get students talking in order for to help them understand why they did what they did; who was affected by their action(s) and how; and what can be done to repair the harm.
My thoughts on whether the five main premises that the authors of "Hacking School Discipline" use in their introduction are correct.
Your students know what they've done. What they're waiting to see is what YOU will do - and here's where things become critical.