Oh my goddddddd !!!
I think teacher shouldn't exclude student out of the class .....
Maybe it is classroom language but it is in very bad behavior .
Then, what will student do outside or what do they feel if the teacher keep them out of the class?
for me , If I have to do this I won't exclude them but I will ask them for standing in front of the class and don't look at their friends . At least he will hear and study together with the whole class.