When should I take my 3000 level core courses?

You should take both Intermediate Micro and Intermediate Macro in your sophomore year, but no later than the fall semester of your junior year. Note that with the exception of UN2257 The Global Economy and UN2105 American Economy, all department electives require both Intermediate Micro and Intermediate Macro as prerequisites, so you will need to take both Intermediate Micro and Intermediate Macro as early as possible. Econometrics should be taken no later than the spring semester of your junior year. You should take Statistics and Econometrics in consecutive semesters. Some electives assume a basic familiarity with statistics and econometrics.