DC (13) is in a WhatsApp group with school friends. A few days ago one of them posted some abusive messages - including racist insults aimed at nobody in-particular, and some explicit sexual references aimed at a particular girl on the group.
The boy then apologised and blamed his older brother (who isn't at the same school) for making the posts while his phone was charging. As all this was in the middle of the night he then "spammed" the board with hundreds of junk messages so the originals would be less visible when others woke up next morning.
The conversation has since moved on without comment from the other students, so I don't know if they scrolled back and read the messages.
But should I report the incident to the school? If I was his parent I would want to know about it, and at the very least I think this boy needs to be advised to get some password protection on his phone.