@Coloradomama: I feel like unnecessarily difficult is rare. Keep in mind that students scale difficulty rating based on the majority of the classes they take. So if one instructor stands out as noticeably more challenging or different than others in a department, then they receive that label of being unnecessarily hard. The reality is that, even at elite schools, many other instructors can be teaching something kind of close to a standard level course (as in is taught at the same level and assessments and assignments are the same as other schools with less capable student bodies).
Most elite schools are going to have several more professors in STEM (than non-elite counterparts) that still have very high standards even versus the elite student body. I personally think that when the teacher is good, gives lots of resources (whether it be study materials, mentoring in office hours), the difficulty of these instructors is totally worth it because you build skills that you would not have otherwise. Again, the difference between instructors with high standards and those considered more medium or easier is often that the latter only requires you to essentially know how to do the problem sets you were already given or to memorize content and a more challenging instructor asks you to take the knowledge and logic of those assignments and then apply it in sometimes a completely different, if not initially, unrecognizable way. In my opinion, it doesn’t hurt to have a few professors that push you to think differently/more fluidly like that (and not just stay limited to the ideas and problems they directly presented in class), especially in science curricula. The reality is that if you do projects in industry or graduate school, they will be more open ended and essentially ask you to constantly adapt your knowledge to a new, seemingly different problem.
More challenging teachers are often trying to develop that skill and the teachers who are good and supporting teaching at such a level believe that students at these selective schools can do it. These types of teachers are the reason I love things like biology and organic chemistry. Had I taken teachers who were more standard in how they test and teach, I’m sure I would have just gotten my grade and treated the course as a checkbox never truly appreciating how one is supposed to think in those fields. Science isn’t always about getting the right answer in a very particular way. The problems you get in real life often do not have algorithmic solutions that are already available/have been applied successfully. I’m a big advocate of lecture and lab components reflecting or encouraging actual scientific thinking as much as possible regardless of the class size. Sadly, many students stick to the belief that a science course and science is just about “the facts” and the proven processes that led to them.
@Momof3kidsau : Again, if the teacher actually tries to support the student through the course, then more rigor and students struggling may indeed be a good thing. Even if we’re smart, always “getting it” immediately is typically not realistic and if all teachers at an elite level or advanced school taught such that their talented student body just always “got it” then you’re assuming that they can go no higher in their abilities. Typically selective schools are academically elite because they have the instructors who are able to even challenge well-prepared students and make them even better. Whether or not one chooses to attend these places and get the full benefits (as in not overly engage in GPA management by simply dodging all hard instructors: Because honestly, many hard instructors are of higher quality. Sometimes easier or standard level instructors only teach at those levels because they are a) lazy or b) don’t have much time to dedicate to undergraduates so basically water it down enough to challenge enough students but also keep as many as possible away from their office hours or TA’s. They basically make the class “meh” enough so that they don’t have to put lots of effort into ensuring a decent success rate) is up to the work ethic and ego of the student.