I got a C in a core class. Should I retake it? I'm a 3rd year aerospace engineering undergrad with an inclination to pursue graduate studies in dynamics and control (ultimate goal of PhD). Until last semester, I had a lazy attitude towards my studies which earned me 3 Bs over the span of my undergrad studies. Last semester, this laziness, personal over-commitment, and poor prioritization culminated in a 'C' and 'B' in two core classes--both of which were in my strong suits of structures and dynamics respectively.

This semester, I have the opportunity to  retake the structures course. Should I retake it?

My primary reason for retaking it is that I'm confident I can get an 'A' (I aced every quiz when I studied) and show mastery of a fundamental concept (FEA). However, my reasons against it are:


It'll take up time that I can dedicate to research for my u-grad thesis
I'm planning to take a more advanced structures course next spring (though this won't show on my transcript since I'll apply to schools next fall)
Retaking the course barely improves my GPA (3.817 vs. 3.811)
My professor suggested that I review and streamline his course notes for future classes


I'm not worried about the B dynamics course. I'm meeting with my prof this week to discuss a way to move forward (I think I'll be grading or providing mini-recitation lectures). However, I don't know what to do with the structures course.
An easy answer, from the viewpoint of grad admissions, at least: iffy grades are a blot... but/and, also, a serious question is about the extent to which "bad grades" reflect you understanding ... of things that need to be understood, not just gatekeeper stuff.

Also, you'll be competing against people who have reasonably-good grades... for whatever that's worth... but/and grad admissions committees will not see much up-side to admitting people who "show" worse than others.

Also, btw, it's not so hard to get good grades in undergrad stuff, even if one isn't ultra-conformist. True, it's also not hard to get iffy grades even when one has a pretty good understanding. But/and (!) in these days when everyone on the planet hopes to make a living as a computer-scientist (for example), not being prey to the standard tropes/weaknesses may be the selling point.

That is, maybe retaking courses to generate better grades that will mask old, not-so-good grades, is worth your time... unless, on a different course, you can do "genius-stuff" ... which makes schooling irrelevant, ... maybe.