I would like to add my accolades in saving $3000, it is an accomplishment that the majority of US households are unable to achieve. source
While it is something, in some ways it is hardly anything. Working part time at a entry level job will earn you almost three times this amount per year, and with the same job you can earn about as much in two weeks as this investment is likely to earn, in the market in one year.
All this leads to one thing: At your age you should be looking to increase your income. No matter if it is college or a high paying trade, whatever you can do to increase your life time earning potential would be the best investment for this money.
I would advocate a more patient approach. Stick the money in the bank until you complete your education enough for an "adult job". Use it, if needed, for training to get that adult job. Get a car, a place of your own, and a sufficient enough wardrobe. Save an emergency fund. Then invest with impunity.
Imagine two versions of yourself. One with basic education, a average to below average salary, that uses this money to invest in the stock market. Eventually that money will be needed and it will probably be pulled out of the market at an in opportune time. It might worth less than the original 3K!
Now imagine a second version of yourself that has an above average salary due to some good education or training. Perhaps that 3K was used to help provide that education. However, this second version will probably earn 25,000 to 75,000 per year then the first version. Which one do you want to be? Which one do you think will be wealthier?
Better educated people not only earn more, they are out of work less. You may want to look at this chart.