As a 19 year old girl in college, the first thing I would do is pay my own tuition and fees so my parent's wouldn't have to. The other thing I would do is put anywhere between $50,000 - $100,000 dollars in a CD in a bank to save for the children I have in the future (so I can put them through college).
The next thing I would do is give $200,000 - $300,000 dollars to various charities and organizations. There are people in the world that need the money more than I do. With the remainder of the money, I would save it in a bank for me to live off of and eventually to get a house and start a life for myself.