@alisha-- Good question. I don't know about the courses they take. But from what I understand, production designing is more about conceptualizing the themes and designs. The production designer will come up with ideas, make some plans on paper but his assistants and model makers will be the ones building it.
There might be some production designers who do more than that. I guess it depends on his or her background. If a production designer has a background in architecture as well, I'm sure that would a big plus and he might be more involved with the building part.
I hope this helps.
Does anyone know about what courses production designers take in school?