So, I'm a judge for this year's IGF student division. (Due to an email mixup, I found out about this two days ago, so I've been frantically playing since.)
Some of the entries I've seen are so amazing that I can't believe it's a student team and not a commercial product. Others are so bad that I wonder why they even bothered submitting. Still others, I never even got to see because they crashed before starting. With this in mind, I present some advice to future IGF entrants (student and otherwise) based on the common mistakes I've seen this year.
Find the fun in the first 30 seconds. I was given 21 games that I had to judge. That means realistically, each game is not getting ten hours of play. If the really cool stuff is on the last level, I might never see it. If the really cool stuff isn't even in the game (say, you're making a demo for an RPG and all you've got is the first dungeon where you have to kill 50 rats), you fail -- make one of the later, more fun levels for your demo instead.
Include level select and other cheats. Suppose I'm playing through your five-level demo, and my machine crashes near the end of level 4. Do you think I'm going to replay everything just to see level 5, or do you think I'm going to assume I've seen enough and move on? If I can jump immediately to level 5 with a level select, maybe I'll give it another try; if I have to replay the entire game, forget it. Likewise, if the first level is so difficult that I lack the skills to make it past, give me "god mode" so I can at least see the rest of your content.
Include single-player mode. Not everyone has a gaming group they can play with. If I'm judging on my own, and you require 4 or 8 player simultaneous, I won't be able to review your game at all. If you add AI opponents that allow single-person play, this at least lets me play around with the mechanics somewhat. If you don't have the time or skills to implement a full AI, have the opponents sit there and do nothing and call it a one-player "tutorial". Either way, at least let me play.
Avoid mods. Just like not everyone has a group of gaming buddies, not everyone owns a copy of Unreal or Half-Life. If your game is a mod that requires judges to have software other than your game itself, it might not get judged by as many people. If you must make a mod, be very clear about it in the requirements list when you submit your entry; this is just courtesy, so that judges lacking the ability to play don't waste time on it.
Avoid crashes. It should seem obvious, but I saw some games that actually crashed on startup! Test your installer on a few "virgin" machines before submitting. These last three points can actually be summarized as one: let me play your game!
Don't overhype in your description. Each game has a brief text description. I read it when I'm waiting for the game itself to download. Some people are really full of themselves, telling me all about how original their game is or how great their graphics are or how fun the game is. Don't insult me; I should be competent enough to judge your game on its own merits, not on your opinions of your own game. This actually has the opposite effect for me; if you tell me how original your game is, it just makes me think really hard about what other game(s) yours is derived from. Unless your name is Peter Molyneux, leave the hype to the marketing people.
Make sure the player is having fun, not the computer. Sid Meier's immortal advice rings true in a surprising number of student games. Your game might have an amazing AI or some really complicated mechanics under the surface, but if I can't see, predict and understand them then I'm not really having fun as the player. Try giving your game to someone who knows nothing about it and has never seen it before, and after they play ask them what's going on. Anything they can't tell you is something you need to work on.
Grow a thick skin. Judges can submit anonymous feedback, and we're told that it's perfectly okay if we're harsh (as long as we're also constructive). No game is perfect, especially a student game, so expect everything you've put your soul into to be ripped to shreds. (If it makes you feel any better, you'll get to go through this again once you get into the industry, when some reviewer for IGN trashes the game that you put the last three years of your life into.)