I'm honestly not sure about using the term "shut up" anywhere, let alone in classrooms but rather than address that (I'm sure you'll get a lot of differing opinions), I recently read an article in The Washington Post on how teachers are using sign language instead of words to limit classroom disruption.

We also have a great video on how one teacher uses sign language in his class. (It's the last video on the page).

I totally agree with both comments above. I think it's very disrespectful to say, "Shut up." I will admit that I have said it a time or two when I am trying to get a point across. I can count those times on one hand. I don't even like for my students to say, "Shut up" to others.

I enforce a strict No "Shut-Up" policy in my classroom. We discuss why people might say it, how it makes the other person feel, and alternative ways at accomplishing the same thing. As with all rules, the key, I think, is in this kind of discussion.

I prefer a no "shut up" environment, instead of a no "shut up" rule I guess. Part of what goes into what I consider to be a successful year is getting through it without ever saying it myself (That would be the last two or three for me). I'd rather say, let's be respectful of each other, and an example is not using terms like "shut up" ("snitch" is another least liked of mine) although there is no way I would feel the need to use that one.

Along the lines of "snitch"...

At our school, we often call on our students to help us "get to the bottom" of an incident. For example, a teacher's cell phone went missing. We brought the school in and talked with the students about the need to find this and if you knew anything to come talk to an administrator.

The push back I hear from students "Well, I don't want to be a snitch." What we talk about with our students is that you are not being a snitch. A snitch is person whose motive for telling on someone is to get them in trouble. We really try to emphasize that you are not getting that person in trouble. You are helping stop them from continuing to make poor decisions. Ultimately, you are actually helping that person realize a mistake that they made and also helping the victim (teacher who lost a cell phone). This all goes back to creating a family-oriented environment at school.

Does it always work? Unfortunately no, but it is a start I know know that it has helped our campus (YES Prep North Central) "get to the bottom" of a number of minor incidents.

I like your point about helping, not hurting. I like to say, look, that is prison talk, and this is a school, not a prison, but that does require making sure that school doesn't feel like a prison to the kids, lol, otherwise I look self-delusional and sanctimonious. A truly deathly combo in a teacher.

Wow! what a great idea - and coincidence! I saw the Washington Post article about signing just a couple of days ago and sent it on to a young powerful teacher who is going through a lot of struggles with chatty, disruptive kids. Thanks for the videos of signing teachers.
As far as shut up...it's not profanity, but it fits in the same category of language that is so disrespectful if feels the same. Long ago as a brand new, emotional teacher (about 100 years ago) I said it in a fit of being so at a loss and frustration--my 2nd grade students looked at me as if I committed the worst possible act of treason and one little one said, Mrs. G that's a swear word! Well, needless to say it has marked my memory bank forever.