I went to a private high school that is not really that selective. My school is usually a feeder to Cornell, sending around 6 each year from a class of 60. However, this year only 1 got into Cornell. Other schools that many kids are accepted to include Fairfield, Union, Providence, St. Lawrence, and Clarkson.
One thing in particular that I think made me stand out was my family situation, and growing up with a sister that has autism, which is what I wrote about for my common app essay.
I also feel that I showed how I excelled in my sports from taking on a leadership role to volunteering to help coach others.
Lastly, I think this was a big factor that helped me get into many of these schools is that I had a lot of real world experience that tied in with my major.