@Dustyfeathers : There are many things…and it comes from the fact that some schools just pitch certain courses or even sets of courses at completely different levels than other elites. Some schools have a different curriculum altogether for many pre-health cores (this has become a more recent development as more “integrated” science courses have been promoted by those in highered). It seems it can indicate a number of things such as the course load being easier. For example, at some schools, the requirements to major in a STEM subject or to simply attend the school are more stringent (maybe there is a senior project requirement, a challenging STEM core, high credit hour requirement). Sometimes the content in the pre-med core classes at some schools is significantly more challenging on average than it is at other elite institutions and then the exams reflect it (yes, many of these places have grade inflation, but at the same time, many of the schools I refer to alread have quite fierce competition because a higher percentage of students have experience beyond just AP/IB credit). Like some schools have moved some chemistry and biology courses into a more “integrated” direction which would make the course more challenging for a freshman or sophomore. Princeton and Yale’s intro. biology course sequence at least touches on biophysics/physical biology aspects which has not been done at most schools. Harvard’s life sciences 1a is some combination of experimental biology, general chemistry, and an intro. to some biologically relevant organic concepts. Some intro. biology sequences that are even “traditional” when compared to those places have a slant toward more modern genetics content and experimental biology that has not quite popped up everywhere (MIT, Chicago, Columbia, WashU, Penn, and some other others come to mind).
Many freshman/sophomore STEM/pre-health students may feel (perhaps rightfully so) that they have a better chance of success in a course where most sections are very heavy in content volume and focus more on regurgitation, understanding, or low level applications to be successful on examinations. A case or problem based biology course may spell for quite the adjustment. Some schools have physics sequences that set the bar a bit higher than other schools (like they’ll only have a calc. based for pre-healths and that calc. based course stresses a higher than normal level of theory and mathematical prowess). The “general” chemistry sequence at some schools encompass some version of real quantum chemistry and also concepts that may only be seen in an advanced or intermediate inorganic course. At least a portion of the organic sequence at some places (Harvard for example) looks more like an advanced bio-organic course at other top schools.
Some schools with unusually challenging organic sequences who have not revamped it into a biology emphasizing course have instructors (or just maybe it is department controlled, I know Harvard closely monitors outcomes and level of its intro and intermediate STEM courses) stress a much higher level of theory than needed to simply know some ochem for the MCAT. They tend to delve deeply into Molecular Orbital theory (and not just basic HOMO-LUMO, name that orbital, but stereoelectronic effects, etc) and other concepts and tools that are more reminiscent of an advanced or graduate level course. The problem types given to students on assignments and exams are on a different planet compared to other even elite schools which are traditional in their curriculum and mainly ask for the standard, tell me the product of the reaction, do some T/F questions, draw this mechanism which you definitely have seen before, perform a synthesis…the tests at the schools I mention, are more application, synthesis, and even creativity based. They are much more focused on getting students to explain away phenomenon or experimental data on reactions or outcomes they haven’t been taught. You are required to derive and then draw a model to explain something away. Some of the harder courses that lean more toward the traditional paradigm make the students deal with very complex molecules, thus forcing them to really understand the principles behind a reaction and not just memorize the outcome of different reactions.
At some schools, these differences may only exist in maybe 1-2 of the pre-health cores, some none, but there are a handful where it is existent among all of the pre-health core courses, no matter who is teaching (again some schools do seem to regulate these courses much more than others). The STEM curriculum, in terms of ease, level of theory, and content stressed at many of these places is likely more appealing to those going into those fields (as in grad. school or industry) for their future. It can certainly be great from an educational standpoint to have pre-meds having to know how to problem solve in various fields at the levels I describe, but it isn’t a requirement and medical schools are very GPA sensitive. Most STEM majors will have the one subject that doesn’t appeal to them and at many schools you can just take an easier instructor or course in the subject and still fulfill the pre-health requirement, but at some places, you just have to deal with a course that may be on steroids and is a nightmare for a person just taking it to fulfill a requirement.
*Don’t get me wrong, most elites are harder than most “normal” schools for these courses even when the course is pitched at a more traditional level even if just because of the competition. At many “normal” schools, the students would on average, struggle through the exams and a curve would need to be applied. At an elite pitching a majority of pre-health courses at a more traditional level, content volume will generally be heavier and the averages still much higher. If you are at a school where most instructors write exams that are at a normal level, expect a near 80 or 80+ average and no curve meaning that you’ll pretty much have to always score near or in the 90s to make an A grade. If you add more content volume or have a “couple” of higher complexity questions on exams, maybe expect 75ish and no or a very slight curve (the same test at non-competitive institutions may yield mean below 60 unfortunately). I am just claiming that some elites have many more instructors asking the already smart students to jump really high very soon. It isn’t just the competition, the instructors are pitching the course differently and primarily in a way stressing skills not as emphasized in HS STEM courses.
It could also be the grading curve. Some elite schools still have a decent percentage of STEM instructors with C+/B- distributions, so students would consider these places relatively grade deflated. However, they are really just less inflated though and honestly, a lot of these schools often are NOT pitching their course at the same level as some of the schools I mentioned, many of which have slightly more generous curves in those weeder STEM courses. Often when I see conversations on here that say: “Well my elite school is so grade deflated compared to that one” in reference to STEM, based on the course content I see from the other school, the comparison simply isn’t fair in the first place. Such comparisons assume that the departments being compared (interschool) have instructors that teach their courses at the same level. Some times it just ain’t true. One school can have a single brutal section, or have most students concentrated in sections run by instructors who pitch the course at a very high level, and another can have no such sections or just one taken by a minority of students.