An application to graduate school typically requires a statement of purpose, and each school has specific requirements for this document. Some may give you a question to answer, while others will leave the topic up to you. Almost every school will require a length of 1-2 pages. (If they don’t state this, they probably follow this guideline anyway.) Keep in mind that they expect your statement to be concise and to adhere to this length. Schools tend to weigh the statement heavily because it shows elements of your personality, as well as your writing and thinking skills—these are critical in graduate school.
Because the statement is so important, you should begin writing it months in advance of its due date. You will then have time to revise it (as many as 10 times) and have others critique it. You may write a generalized version of your statement in the summer, and then a more specific statement for each school you apply to.
Before you begin writing the statement, you can use a variety of questions and tools to focus. Brainstorming is a highly effective tool, encouraging you to write your random thoughts down. Start by asking, “Why do I wish to go to graduate school?” Then list examples of instances in your life that have directed you to this goal. Examine your resume and select a few key points that you can elaborate on, backing up your assertions.
Keep in mind that you should avoid simply restating your resume. For example, you may state that you are interested in aspect of cognitive science because of the nuances of. Then you back this up by saying, “My experience in So-and-So’s lab has taught me (encouraged me to, etc.).” Perhaps you can give an example of when you excelled in the lab, or you can describe the first time you had that YES! sensation when doing research. Remember, these are just preliminary suggestions— your brainstorming will produce different results and a better fit for you.