Hey there!
This depends heavily on what you want do use your iPad for.
If you want to do anything that's close to getting some (paper)work done, I would definitely recommend the iWork office suit, though it's only living up to it's full potential if you have a Mac with iWork on it.
Then again, iMovie and Garageband are incredibly fun if you like to be creative and want to do some movie/music editing (or even compose your own songs).
Also, there are great News-Apps for the iPad. I personally like the International Herald Tribune, but there's really one for everyone's taste.
The App I (as a student) use the most, is probably iStudiez Pro. It's a great calendar and organizer. It's got custom versions for the iPhone and the Mac too and you can sync them perfectly so that you're always up to date on each device.
Still, what Apps you want to use depends on your personal taste, I recommend browsing the App Store a little bit and looking for what seems interesting. The user's comments can help very often.
Yours
Kontext
