Three courses (ECON BC3033, BC3035, BC3041) comprise the theoretical core of the economics and political economy track majors. It's a good idea to take these courses early on because they provide essential background for the more focused upper level elective courses. You can take them in any order. Many students find that they achieve a more balanced schedule by pairing one of the theory courses (which involve problem sets and exams) with Theoretical Foundations of Political Economy (which involves writing papers).
Intermediate Macroeconomic Theory (BC3033) is about the economy as a whole, including such phenomena as unemployment, inflation, and international financial adjustments. Recitation sections and problem sets are an integral part of the course. ECON UN3213 Intermediate Macroeconomics (at Columbia) is also acceptable to meet the requirement.
Intermediate Microeconomic Theory (BC3035) is about the behavior of individual economic agents, which means households (people) and firms (businesses). Recitation sections and problem sets are an integral part of the course. ECON UN3211 Intermediate Microeconomics (at Columbia) is also acceptable to meet the requirement.
Theoretical Foundations of Political Economy (BC3041) is about the intellectual origins of modern economics as well as the historical origins of the modern economy. You will read and write about a selected number of the great texts of economics including typically Adam Smith, Thomas Malthus, David Ricardo, Karl Marx, and John Maynard Keynes. There is no Columbia equivalent to this course.