I have met many a teacher who yells at children for them to stop yelling. And just like parents every teacher has their history to deal with and will rise like magma when they are pulling out their hair. As Waldorf teachers, we are given the image of hanging up our hat when we enter the classroom, leaving the personal behind. Did not always work for me.

My wife would complain when someone she supervised was acting out, or maybe two. Yeah, try fucking 30 acting out!:)