For the most part, they are attentive and appropriately dressed in class. I was wondering whether the students at my school (a middle-of-the-pack large public university) were somehow more refined than average. I find this proposition doubtful, since I did graduate school at the nearby so-called "elite" university, where my experience as a teaching assistant was similar. However, after reading "Rachel at the R1", I suddenly realized what the difference might be.
Both I and Rachel are faculty members in the sciences; Rachel and I both like our students. Meanwhile, when I read the "student behavior" complaints, they generally have keywords (like "doing the readings" and "class discussion") that indicate the poster is in the arts or social sciences. This observation is, of course, informal. And I'm not trying to provoke a science-versus-arts flamewar: the students are different, one group is not necessarily better than the other. RYS could have a disproportionate number of posters in the arts, and the science types would complain more if given the opportunity. But that doesn't stop me from suggesting a theory.
Science education is not collaborative. There is no discussion; instead, I teach and the students listen. There is not much point in a student arguing that E should really equal mc cubed, because that is verifiably false. This mode of interaction reinforces the authority of the professor and promotes conformity among the students. The authority relationship of the professor over the student is thus reinforced, which may lead the student to act more deferentially towards the professor.
I must say that I would beg to differ with the writer above. I am a graduate student in Mathematics at the University of Connecticut and have run across many students that do not care to read the book and try the exercises before they come to class. The students constantly complain that I do not go over every type of problem they see on the homework, even after I've told them that this would be impossible and that if they have questions they should come to office hours.
They call me "Dude" and "Hey, You." (I dress up to teach, too. Most days a button-up shirt and a matching pair of slacks.) They always ask me if the material I am discussing will be on the exam. Basically, the gripes of "Arts" instructors may apply to "Sciences" instructors, too. I also take offense to separating the academic fields of study into two groups, called Arts and Sciences. It is utterly absurd because there are many Mathematicians who would consider what they do as "art."