For example, one great example is Eisen versus Yedvobnik for cell biology (an “intermediate” biology course): Eisen’s course is theme based and taught completely based upon primary scientific literature presentations by students (book is only a reference for those who may not understand the publications much), case studies based upon the literature, and maybe a lecture in between modules. Exams consist of only short answer questions and are based on abstracts usually pulled from recent publications (often Nobel Prize Winning) having something directly or peripherally related to what is covered in class. These questions ask students to derive models and design experimental set-ups/tests with expected results that build upon what was already revealed in that abstract. Yedvobnik’s course is primarily traditional lecture, uses the textbook, integrates maybe a few simple level PBL items. Tests are primarily on specific details in pathways and phenomenon, and have very few items requiring high level problem solving or thinking in comparison to Eisen. Primary literature is excluded from that curriculum. If Eisen’s was labelled as honors…that would be a dramatic under-statement.
You don’t take it if you want to know “more stuff” so much as want to learn aspects of that field in a completely different way. When Eisen taught general biology (with no honors label, same label as other courses), even then, his courses differed by that much. No lectures, all challenging case studies, 1 writing assignment (on top of the case study per week- the week’s material was turned into a disease of the week type of case study that groups had to write up) and one group was assigned to present the DOTW case each week. Other sections taught different material, and used lecture and some simpler active learning activities ever now and then. Eisen used purely short answer w/experimental design oriented questions and abstracts (and again, this was for freshmen) whereas many others were still using lots of or pre-dominantly multiple choice items, with many of those MC items being not so high level. Again, the approach to learning and the focus of the teaching is just very different. Eisen’s class is trying to build much higher ordered thinking skills (and not just throw harder and more content at students) and others were kind of classical biology courses with a focus on detail and maybe some very basic level applications.
In either one of the “Eisen” cases, even a non-biology STEM major may benefit from taking him, so “necessary” or not, he did well enrollment wise back then. Learning how to think those ways in STEMs spills over to success in STEM (and non) divisions outside of biology. If it were simply teaching in more depth and maybe then asking students to do similar tasks as other sections, but with harder/additional content, it would probably not even be worthwhile to a major. I do indeed know many schools where what you said is the case, but it ain’t at Emory (or most highly selective universities or honors programs in decently selective universities). I would really avoid such generalizations or go forth and define what you perceive as “more in depth”…not everyone would agree with such definitions. Again, the differences cannot simply be described as “more in depth” which suggest notable but ultimately subtle differences in content. That type of thought and not knowing or investigating the real differences will lead many to either be dismissive of the course or go into it with misguided expectations.