Just appreciate that they are talking about it with their parents
See, we are only as sick as our secrets. The moment they start hiding it, they might progress deeper into these type of things. These type of problems grow in the dark, and tend to cure in the light.
I am.not saying that one will not mark drugs as dangerous or anti-social activity. But flying off the handle & ,raving and ranting, blaming this and that person will only convince the kids that he/she shouldn't have confided.So, behave cool, assertive, firm but cool.
And plan a family outing, some fun activity in near future