In addition to near-perfect or perfect test scores and grades, you will be expected to have taken the hardest possible curriculum, and to have shown intellectual curiosity by doing something in your chosen field that is above and beyond your school curriculum. For instance, if you have the chance to take an online course not offered at your school, or to participate in activities outside of school, you should consider doing so. Your extracurricular activities, especially those related to your major, are very important for MIT. They want to see that you are so excited about your major that you engage with your subject outside of school. For instance, if you plan to major in math, tutoring local kids in math, or engaging in math competitions, will show that you have demonstrated initiative above and beyond what is required, which shows the spark you have for the subject.

Your application itself is also very important to MIT. It is often said that students at MIT have a sense of humor. The supplemental questions are different from those of other schools in that they want to learn about your personality and what you value. Spend a lot of time on your application, including your supplementary answers.  You should also regularly look at the MIT Admissions blog, which is written by current students, and which has excellent tips.

MIT also puts lots of weight on letters of admission. Make sure you have two academic teachers, one in math or science and one in humanities, language or social science. Make sure that your teachers can say wonderful, detailed things about you.