Every Tuesday at 11.30 I have statistics in Kane 120. For some reason, our section of 30 people was put into a 200 seat lecture hall. The end result is that 15 minutes before our class is over, students from the next class start filtering in to sit down. No matter how quiet they are, they still have to open and close the doors, put down their bags, take off their jackets, put up the folding desks, and settle in. Often they open their bags to pull out textbooks or hw to work on. All while my TA is trying to explain to us about variance, bonferroni, and main effects of interaction.