In these of unleaded fuel, you may use spark plugs until the electrode erodes away. Every-so-often, check the center electrode for a sharp edge. As slowly rounds off, file it sharp.
Admissions officers look first at test scores, the rigor of the courses you take, and your grades in those courses. After that, they are interested in a student's extracurricular activities -- in other words, how you spend your time outside of classes.
The most important components of the college application include the essay, extracurricular activities, leadership focus, and accuracy. The essay is the part of your application that helps you become three dimensional: You become more than academic statistics of GPA and test scores.