As everyone has said, you don't need the internet for (almost) all VCSes. That being said, if you're unfamiliar with whatever system you are using, I'd highly recommend finding a nice GUI, since you won't be able to fallback to whichever site you'd normally use.
SVN is pretty well supported by IDEs, and you can run the server on the same machine. That being said, if you plan on developing radically different versions of code, or if you're developing on more than one computer, you probably want a distributed system.
Git and Mercurial (hg) are both relatively new, but awesome. They're pretty comparable feature-wise, especially at this level.
Github is an amazing service, but really isn't too applicable for FRC, especially if you'll never/rarely be online.
Last I checked, hg has better Windows support, however. If you're working on Windows, which I assume you are, it may be enough to tip the scales.
I've also seen recommendations for darcs & bazaar, which are both great, but don't offer anything special that'd be applicable to this situation. Git & hg both have tons and tons of tutorials and guides available. Especially since I assume everyone is starting fresh, it makes sense to go with the most documented option.
Nibble's tutorial seems great, and would be a feasible way of working on it at school while being able to take it home (where you can then back it up on github & share it with your fellow teammates).