Juuling/vaping is a huge issue for us here (large suburban public high school, Northern California). It's really hard to detect because the vapor is usually odorless. I have never seen vapor in my class and would FREAK THE F OUT if a kid tried that on me. I do have students who always have to "go to the bathroom" around the same time and I have my suspicions, but no proof. It's scary because they can put other substances in there besides nicotine and there is really no way to detect it. We have a part-time School Resource Officer, but no drug dogs. And, yes, it is possible to expel a kid for drugs, but it has to be a major offense, like intent to sell/dealing. Simple possession is usually five days' suspension (aka vacation). It's a huge problem.