What happened to the years?

What happened to the years where our lives did not depend on everything we did in or out of school? Can I not just be a kid? Not anymore. I am going to be 18 in a couple days. I will turn into that adult, ending what I know of being a teenagers. I can vote.I can leave and be on my own. No one can legally tell me what to do (even though I will not be doing that). I am on of the old people in my class. I will graduate at 19 while some will still be 17. I have always been that way, ever since 1st grade. I can not explain how it feels to be older than everyone else. I know it is not a huge deal, but I have always been mentally more mature than others. I feel like I get along better with college students than I do with students at school. I like being an older sister to younger students. I guess being older has the benefits of you can say you have already done this or that. But sometimes you feel like you do not belong. Like you are not smart enough or good enough to be in your grade, so let's put you in a lower grade that you can do alright in. But you learn to fit in, especially after so long. But all the years I have been in school, so many things have changed. I can believe how different everything and everyone is. It is hard to wrap my mind around the thought that I am about to be an adult and yet being a teenager was only so long ago. We always dream about of future and what we are going to do in life. We prepare and take all measures to make sure the future is set out how we want it. But now all I want is to relive all my young years again. To be a kid.