Depends on your needs. As mentioned above, you can use Bootcamp, a built-in application that comes with every mac, to install a version of Windows if you find out you need it later on. Also, there's an official Microsoft Office Suite available for OSX, so you can buy that to increase the compatibility of your documents with other classmates (document compatibility is one of the few reasons I hold on to office at all...) if you need to.
Software wise, I think you'd be fine with either a Mac or a PC for standard college courses without the use of Bootcamp (I can't comment too much on major specific classes, since the OP didn't discuss them). If you're looking to get a laptop, I'd recommend an Apple laptop. I've personally found the longevity of Apple laptops to make up for their cost (I still use an iBook that's over 10 years old for most office-related tasks...). If you're looking for a desktop, I'd shop around both fields and do some price comparisons.