It's the combination of your grades, MCAT scores and application that gets you an interview at a medical school. Schools vary on the emphasis they place on each one, but they all look at each piece and the total package.
The New York Times reports that medical schools are starting to take a holistic view of student applications. Along with the top scores, they are looking for the top personalities. They want to see a background that says the student is a leader and has a passion for learning and working with people. You'll have the chance to describe yourself in your application's personal statement and essay.
Beyond your grades and test scores, schools will look at your background and experience. They want to see your dedication to science and medicine, but they also want to see what experiences have made you the person you are. These experiences will be the mix of academic and extra-curricular activities in which you participated.
Ask yourself what makes you stand out as unique. There will be many applicants who say something like, "I worked in a nursing home as an orderly between my junior and senior year." Of more interest to the admissions committee would be, "I ran a program at the local boys camp to teach CPR to the kids." Or, "I ran a blog for three years on how to select the best daycare for your children and how to help them get the most out of their experience."
Think about the traits that make a good physician. You may note persistence, empathy and curiosity. What experiences have you had that fostered those traits? Focus on the things that contribute to your desire to become a physician. You'll likely have many, and not all will be health-related. Your experiences taking care of a family member, traveling in a foreign country or volunteering at a food bank are some of the things to include in the essay, because they helped you form your attitudes and opinions.
Once you have all of your materials together, create a professional-looking presentation. You can have the materials printed locally, or with a little research, you can find quality options for printing online. Each application packet will be a little different, so make sure each looks professional.
Schools are looking for a new class of students, and this is your time to make your application shine. Good luck.