There are a lot of students applying to college anymore, so most likely you'll need more than just good grades and test scores to stand out from the rest. I'm not saying that you won't get in if you don't have any extracurriculars, but they sure can't hurt. I had Band, foreign travel club, forensics (public speaking), odyssey of the mind, national honor society and various other things on my application. there has to be Something that you're interested in, or start a club of your own? That'd look really good on an application. Good luck
