You’re being trained as an economist in the neo-classical tradition: a little bit in principles, and much more so in this class. That’s not just because of the higher level, but also because the neo-classical paradigm has been the predominant force in overturning Keynesian macro over the last 45 years.
Anyway, Matt Yglesias wrote an article for Vox* entitled “9 Things Only Neoclassical Economists Will Understand”. There’s not much to it, just more of a list, with one-liners.
The thing is, for your purposes, several of those come up in this class each year. Noah Smith, an assistant professor at Stony Brook, has written a follow-up for Bloomberg View entitled “9 Economics Mysteries Explained” (he also blogs at Noahpinion).
Read them both as a way to start getting conversant in what economics students do at higher levels.
* Yglesias is a public intellectual — not an academic, not really a journalist, but someone who writes a lot of highbrow stuff. I guess I’d describe Yglesias him as a liberal who isn’t afraid to criticize the Democrats, or admit the Republicans are right sometimes. Vox is a site that’s kind of half-way between blog and legacy media magazine: big ideas, big name authors, long articles.