What would you say or do in this case? A student made a negative comment about a piece of work and I answer that, "I don't like that comment, stay in break to speak to me about it" (it's not the first time he's been negative and I wanted to speak to him about it) while another lets out peals of laugher that a friend has to say in break. I've used the line, "If you think it's funny, you can stay too." but it's getting old and anyway I've noticed sometimes others will also laugh in response to him staying (like a chain of laughing at those who stay in break) Obviously it's very inappropriate because it's like laughing at the discipline. Then of course they complain they have to stay in break because they were "only laughing" and "it's not fair". How do you think is the best way to approach this or explain so it's clear for them that this is not on!