Changes

My little sister got accepted into the NJHS tonight. And as I was sitting and watching her, I remembered myself a few years back being in the same seat as she is in now, and how I am such a different person than I was at that stage in my life. People change so much in the years of middle school and highschool and we're all aware of it. We've gotten new friends, changed our style and image and we've gotten involved in certain clubs and activities. Some people get more socially involved than others by participating in sports, while others would rather keep to themselves and stray away from the school activities. What is it that leads us to who we become or which "group" we are part of in highschool? Is it our choice in friends? Is it peer pressure? Or is it that we follow our true interests and therefore take part in things that we like, such as band, or football?