Three of my classroom walls are brick while the other one is a fake wall (a sliding fabric door) like those between 2 rooms that can be closed for 2 separate rooms or opened for 1 large room. My school (middle school) really pushes for student collaboration which I am completely fine with. The teacher on the other side of the wall is really loud (we can hear her all of the time). My biggest concern is when I have pre-AP classes, she has basic co-teach. She is constantly telling me my students are really loud and it distracts her students. It doesn't help that pre-AP does completely different activities then her students. I am trying to have my students collaborate but she says she can hear them even when they are using level 2 voices. I don't want her students distracted but I am also tired of not being able for my students to collaborate because of the noise. I have filing cabinets and bookshelves against the fake wall to block out noise but she still swears we are too loud. My administration has come in several times to observe when the students were collaborating and they haven't said anything about the noise being out of control. I have tried to have the students away from the wall but there is simply not room for everyone to be away from the wall. Thank you for the suggestions.