<p>Not unusual. As a 16-17 year old UW-Madison college freshman son took an elective Linguistics course that was cross listed with Anthropology and had both 101 and 301 course numbers (different discussions). Four ways of signing up for the same lecture. Son took the 301 version- why not? 100s and 20’s level courses are not allowed to be taken by grad students there and I believe grad students might not get grad credits for 300 level courses. Courses in the 400s to 600s can be taken by both. 700s are entry grad level courses but Honors students can satisfy the thesis requirement by taking those- useful for math majors especially. 800s are strictly upper grad level. As you can see there is quite a bit of overlap. </p>
<p>I doubt the upper level/numbered courses are “weeder” courses anywhere. Some students will attempt them and not do well simply because they are not ready for the material, not because of any harsh curve. You expect the upper level courses to be more focused and require a lot more background. I suspect there a lot of “wanna be” students in many general/introductory courses who just can’t handle the course material like the majority of students. Chemistry and premed students come to mind, especially at a school that doesn’t have 3 or more intro Chemistry courses that allow the best prepared/possible majors to separate out. Just because students want to take a course does not mean it has to be watered down to accommodate everyone.</p>
<p>You do not march through college with your age/class peers like you might in HS. You choose the classes you need and want. For undergrads by the time they take their top level major courses there will be overlap with grad students who didn’t get the course material as undergrads. Eons ago I recall some upper level Chemistry courses with both grad and undergrad students in the major- no idea who was who of those I didn’t already know, nor any different grading mentioned.</p>