I'm back in school after a 5 year break, and need to get back up to speed on my calculus. I took it in high school and did very well on the AP exam, and have taken Calc II twice now, but wasn't even remotely dedicated to any of it, so I got a C both times. I am currently taking a class titled "Introduction to Modern Mathematics" which is required for all math majors at NCSU and focuses on proofs while introducing set theory and whatnot. I am most likely taking Calc II again this summer as a refresher, but just realized that I could also take Calc III as we have two summer sessions. Doing so would allow me to take differentials this fall, along with Intro to Linear Algebra and Intro to Modern Algebra. If I don't take Calc III this summer, I can still take the Linear and Modern Algebra classes this fall, and will merely have to postpone differentials until next spring. What do you think I should do?