1. Push the Language in This OptionI've never been a fan of the wording of essay option #3, for if you followed the guidelines too literally, you would end up with a bland essay. The words "indicate" and "describe" suggest that your essay does not need to demonstrate any critical thought. However, a good response to #3 does far more than "describe" a person's influence on you. You should examine why the person was influential to you, and you should analyze the ways in which you have changed because of your relationship with the person.
2. Think Twice About Essays on Mom or DadThere is nothing wrong with writing about one of your parents for this essay, but make sure your relationship with your parent is unusual and compelling in some way. The admissions folks get a lot of essays that focus on a parent, and your writing won't stand out if you simply make generic points about parenting. If you find yourself making points like "my Dad was a great role model" or "my mother always pushed me to do my best," rethink your approach to the question. Consider the millions of students who could write the exact same essay.
3. Don't Be Star StruckIn most cases, you should avoid writing an essay about the lead singer in your favorite band or the movie star who you idolize. Such essays can be okay if handled well, but often the writer ends up sounding like a pop culture junkie rather than a thoughtful independent thinker.
4. Obscure Subject Matter is Fine
Be sure to read Max's essay
on option #3. Max writes about a rather unremarkable junior high kid he encountered while teaching summer camp. The essay succeeds in part because the choice of subject matter is unusual and obscure. Among a million application essays, Max's will be the only one to focus on this young boy. Also, the boy isn't even a role model. Instead, he's an ordinary kid who inadvertently makes Max challenge his preconceptions.
5. The "Significant Influence" Need Not Be Positive
The majority of essays written for option #3 are about role models: "my Mom/Dad/brother/friend/teacher/neighbor/coach taught me to be a better person through his or her great example..." Such essays are often excellent, but they are also a bit predictable. This essay, however, is about a "significant" influence, not necessarily a "positive" influence. Max's essay
focuses on a kid who is explicitly not
a role model. You could even write about someone who is abusive or hateful. Evil can have as much "influence" on us as good.
6. You Are Also Writing About YourselfWhen the prompt asks you to "describe that influence," it is asking you to be reflective and introspective. While an essay for option #3 is partly about the influential person, it is equally about you. To understand someone's influence on you, you need to understand yourself -- your strengths, your short-comings, the areas where you still need to grow. As with all the essay options, you need to make sure a response to #3 reveals your own interests, passions, personality and character. The details of this essay need to reveal that you are the type of person who will contribute to the campus community in a positive way.