On business schools:
Business undergrad and business grad schools are worlds apart.
A decent business undergrad will have a focus in finance, marketing, or accounting available (undergrad business management degrees are worthless) and will have a second major or minor in something else (STEM, economics, music, arts, ANYTHING) that will make them more well rounded and attractive for employment.
That said, the stuff that is taught there is incredibly basic. I'd argue a lot of it could be covered as a minor instead.
Business grad schools can also be very useful for learning how to parse data, apply organizational theory, and explain financing models that wouldn't really be readily grasped by undergrads. There is, of course, the networking opportunities available that come with going to a good grad school.
I did a business undergrad double major in International Business and Finance, and I recently finished a business class at the grad level (I'm not an MBA, though). This is just what my experience tells me.
