I'd leave chemistry off the list: lab work is essential, and very few individuals have the money or the permits to obtain the chemicals you work with in a chem-

I'd leave chemistry off the list: lab work is essential, and very few individuals have the money or the permits to obtain the chemicals you work with in a chem-majors class. I don't know biology well enough to talk, but I suspect that molecular bio at least suffers from the same problems as chem. And you can self-teach physics theory, but experimental physics can require some very specialized and expensive equipment. Not to mention the opportunities to work in research labs, which is where I did most of my education...