Law School Classes One Should Definitely Take If One Wants To Practice in the Area:

Last year I posted, and asked our readers, about classes every law student should take. A reader now asks a related question:

I'm not sure what field of law I want to practice so I am constantly wracking my brain trying to figure out what classes I should take as my 2nd and 3rd year electives. Although, after studying law for a semester, I am more comfortable with the idea that by spending enough time reading hornbooks and extensively researching, a lawyer can start to practice in a field in which he didn't take a single class while in law school, I am concerned that there may be some field(s) of law in which it might be significantly harder than others to do that. I'd like to know about that so that I can weigh taking classes in such an area....

Any thoughts?