you can get many answers on this one and i don't know how small the amount of money is you got. If it has to be fast like in a years time your options are the forex market, options and maybe small caps at the Nasdaq.
There's always risk involved with investing and trading but look at it from the bright side: your chances of succeeding - if you know what you're doing - is 50/50 which is way, way much better than casino gambling and the lottery. With investing the odds seem to be somewhat better.
For trading and investing a must is that you're educated about the subject. Please avoid people who make promises, there is no such thing as promises or guarantees. If there's a catch then you know something is up. You increase your chances significantly if you develop an understanding of the market and the tools of the trade.
Some might say investing is safer than trading, but this is rather relative since therea are also safe trading systems. Depends on how you look at it. Investing implies a long term strategy but the rewards are smaller while trading may have higher risks but the rewards are much larger. Risk is dependant on the individual and you therefore need to develop a trading system of your own if you want to grow your money fast with high leverage. Today online brokers have practice accounts available to learn the craft without risking a dime. I just hope you're not desperate and broke. Scared money rarely wins...
If in the end you rather invest than i can recommend stock funds with Fidelity and the Soros Quantum Fund. They've done very well in the past 20 years. I'm not so sure about mutual funds sicne i've heard several pro investors and brokers claim that those funds are in a waterfall pattern for the coming 10 to 20 years, in other words they will hardly be profitable...
On Friday 8th December, the NFP report is released and the USD always makes a large move at 8:30 am (NY time). A lot of people make lots of money in the forex with this news release, since they know that price almost always moves up with a currency pair like GBP/USD or EURUSD... trading the non-farm payroll is the fastest way of multiplying your money.... this is information not a recommendation.
open up a free gbpusd chart and be ready to watch it happen on friday the 8th....