Do some research and find some interesting company that will soon have an IPO or initial public offering and if its hot enough, it will jump quickly in value and then you sell after a couple days after the hotness of the stock wears off. Be cautious of the risk involved in stock but this is a quick way to increase your investment. You should consult with a local stockbroker.

If you can afford to lose your money or are a gambler, then go ahead and invest in the stock market if you already know how to pick stocks or willing to learn a little.

If you want to play it a little safer then have your bank setup a mutual fund based on your needs and time, they will probably charge some maintenance fee, but is very minor.

If you want to play it safe, then buy a Certificate of Deposit.

Gold

Index Fund , Dow or S&P