Ok, today was the last straw. Ever since September my students have been using my pencils, pens, tape, markers, paper, and whatever else one can think of that would belong to a teacher. I walk around the room and see them using my mechanical pencils. I take it away from one and the next period another kid has it. They erase the board without asking and put all of the papers on my desk into random piles to the point where I don't know where anything is. Today, as I was getting ready to leave at 3:30 I noticed that my classroom keys were not on my small group table, which is where they had been all day. Now the keys are attached to one of those plastic spiral wrist chains and the kids, mostly the girls, love to play with it. There have been other times when one girl had taken it to lunch and returned it saying that they forgot it was on their wrist. I have spoken to them about not touching my things and yet they continue to do it. Now the keys are missing, I don't know who took them, and I am so **** pissed. I'll be even more pissed if I get written up for losing the keys or made to pay for them to be replaced. I am fuming!!! What should I do tomorrow to resolve this because right now I just want to tell them off. What do you do in your classroom to prevent your students from using your items and from touching your papers?