Hi Elly, i guess it is a more of a challenge when you are substituting, because you don't know the students. If one or two students would continually be disruptive during the class I would face them and ask them if there was a problem that I'm maybe not aware of. And if their answer would be "no", I would ask them to quiet down as we are all here to learn. I would not tolerate them continue being disruptive "for fun."
I don't really like to send students out of the class, because I feel they're missing more information. I would only do so if I would feel threatened. But then I would call security. So I usuallly ask them to be quiet and pay attention to the lecturing. I think sometimes students behave this way just to place the attention on them. But make sure to take up their names and write a note to their instructor about their behavior.
