[drunken monkey]

property is one of the only constants where money is concerned.
it's not without risks but depending on how and where you do things, you are pretty much guarenteed good returns.
only real big problem is where to find the initial capital to buy your first two or three houses.

seeing as how you are a kid looking to invest money, i'm going to assume that you don't have £180,000 or the equivilant to buy a flat/small house with...

in terms of savings accounts, I'm not sure if you have them over where you are but here in the UK we have lots of different limited access accounts where you have to give notice if you want to withdraw money. Sounds like a pain but if it's a pure saving account, you won't touch the money anyway. The upside is that you often get much better itnerest rates. Look into any special accounts they might have. We also have some accounts here that give you a % bonus at the end of the year if you don't touch the money so have a look for that sort of thing.

stock is.... complicated.
while in general if you just buy into pretty much secure companies you're more or less going to make money on the shares over a long period of time but you're never going to be sure if that increse in share price is going to beat interest rates...
on the other hand, short term stock playing requires a lot of time and effort (and inside knowledge) unless you get a broker to do the work for you but even then, that's not guaranteed and potentially dangerous.