Of course kids are always kids; they would really play when they are given the chance to play now it is up to the teacher or instructor of any training to discipline them. If you can’t control them or they seem like they are not obeying you. It is your strategy has a problem and not them; maybe you should change your strategy so they will be able to follow your instructions.
Now, I don’t think that going to CR for nature’s call is an attitude problem if you seemed to notice that they are doing it frequently while either inside of a classroom or in training, then you should call their attention, talk to them in a nice way and imposed a rule that is clear to them. And of course you should be fair, whatever the rules, that is imposed to them should also be the rules of everyone.
If you can’t bear it anymore, then talk to the parents. The parents will talk to the kids so everything will be clear.
In my case, I don’t think you told me that my kid has an attitude problem because if you had I was then able to correct her beforehand. Or maybe, are you just making an excuse again?