After consistently losing the web award at Florida regional for the past four years (and I say this in a positive way, without hard feelings), let me share some of the things that
do not work:
Logo violations: I know, "no big deal". Its a pain to follow, looks crappy... but its just not worth getting points off for. We have had minor FIRST logo violations on every theme we have used to try and make it match the background. Mind you, these were not obvious or unsightly... they actually look much better and are more readable of the usual white box approach. However, the judges aren't given wiggle room for "it looks good, but its violating rules". It is a hard and fast rule, so
just blindly follow it. You can take some creative approaches to make it match, such as
http://www.team1902.com/ has expertly achieved.
Crappy navigation: It doesn't matter if you have over 9000 pieces of content if they can't find it. Create a simple and logical way to find content on your site, and try to stick to the minimum that fulfills all the rules - make it amazing, and well organized. Only when your root required content is considered "perfect" move on to creating more pages. Note that creativity isn't punished (and is sometimes rewarded... 1065's Spanish translation in 2007 comes to mind), but time is limited and is better spent meeting the main requirements.
High bandwidth multimedia: While probably everybody here is running on highspeed connections, keep in mind page load times and the amount of bandwith you're using. Creating two different versions of your site is impractical and a waste of time in my opinion, but just keep in mind as you design your pages and layout how long it will take to load. Having videos auto-play is frowned on, and you need to test your site on as many platforms (FF/IE/Opera - Win/Mac) as possible.
http://browsershots.org/ can help with this - you just put in your web address and it takes screenshots on different platforms for you automagically. And as a given, keep profanity off of your site.
Gorgeous layouts: While this is the "fun" part of website designing for most people, this is NOT the place to spend your time. Content > looks, at least according to the web judging. Its very easy to dump your life into making your site look great, while still having nothing of value on the pages. Don't get me wrong, its important, but either write the content yourself or get someone on your team working on it ahead of starting on through redesigns.
Upgrading in the middle of season: If you are running a CMS based site, such as Drupal, Joomla!, PHP-Nuke, etc, don't upgrade unless you absolutely have to during the build season. Wait till summer! I know most web designers won't heed this... but no matter how much you plan ahead and backup (which can never be enough) - something will go wrong in the process. The way web design usually works is that nobody says a word until its "done", or if it breaks. And you will get a lot of the latter. If for some reason you absolutely have to upgrade, make sure you have a good fall back plan. Download a FULL backup from your host ahead of time so you can restore the site overnight if need be. This also applies, even more so, with during the judging period. Try your hardest not to install new features, plugins, themes... don't touch it! Work on content, create news stories... keep it simple! Otherwise things
will break.
Not following the web judging chart EXACTLY: This cannot be stressed enough. If you look at your site and say "oh, thats good enough", it isn't. Make it so that without a doubt, without a second thought, it is clearly met. Again, this cannot be stressed enough.
THIS IS WHAT WINS YOU WEB AWARDS!. If you want to win, follow the chart Michelle posted. They go by it exactly. Word for word. So just, again, blindly follow and make them happy. Have other students on the team to be critical and judge it following the rubric.
If you follow these not so simple suggestions, you will win a web award. Its so hard to not get distracted with interesting features or making a beautiful theme that these are heavily neglected points. It all just depends on how bad you want to win.. you don't have to put in more time, just relocate your energy to other areas of the site.
Good luck to everyone in the future, and I hope this post helps some aspiring web designers on teams out there!