The most important thing you'll need to get into animation school, though, is a portfolio. Many have the misconception that you won't produce a portfolio until after you've completed animation school, but entry requirements often require samples of your art to demonstrate your talent and whether or not you'd be suited for the school's program. If you've taken art classes in secondary school, many of your projects may be suitable for your application portfolio. This can include everything from still life drawings to figure models, motion studies, and character studies.
As with a final professional portfolio, though, you should always consider good taste in selecting your pieces, and showcase your best work. Some schools may ask for a specific number of pieces in certain categories. There likely won't be a category for bikini babes.
If you don't meet the requirements for the sample portfolio, there's nothing stopping you from taking the time to create the artwork needed to demonstrate your talents. In fact, if you begin researching the schools you want to apply for before you graduate secondary school, you should be prepared well in advance - but if not, there's nothing wrong with taking a semester off to get ready if it will help you gain entry into the school you really want. It's easier to make up an extra semester or quarter than it is to recover after all your top schools have rejected you because you weren't ready.
If you've dabbled in animation or 3D modeling prior to applying for art school, include still prints in your portfolio where it's allowable. If you have the chance, slip a CD or DVD with video of your animation and modeling work into the portfolio, to demonstrate that you already have a foundational background. You don't need to create anything as complex as a demo reel; just a quick thirty-second sampler. Stills of the material on the sampler should be included in your portfolio, in case they don't watch the video - and just to be safe, make sure they're appropriate for all audiences.
Just like with a standard college, having good secondary school grades and standardized test scores will make a big difference in your eligibility. If you and another aspiring animator are equally talented, but you're an honor society student with a 3.9GPA while they have zero extracurricular activities and a 2.4GPA, you'll have an advantage - especially when there are limited slots for admission.
Many schools often ask for a personal essay, as well. You should focus your personal essay on your career goals, your interest in animation, your reasons for choosing their school, and why you would be a good fit, with special mention of any particular achievements that might impress, or truly visionary ambitions. More than anything your personal essay should be heartfelt and well-written. Make sure you have your friends read it to help you proof it for mistakes and make it as strong as possible, sot hat you present yourself as someone disciplined and prepared to do their best.
Beyond that, everything is about sending out applications (on time, ahem), crossing your fingers, and hoping. Sure, you have to worry about housing, funding, and just about everything else...
...but you can save that for when you're already holding that admissions letter.
