NEW YORK (CNN/Money) - I'm a third-year college student and my parents have given me $10,000 that now sits in a low-interest savings account. I'm considering investing it in mutual funds, but given the uncertain economic outlook, I don't know whether to leave the money where it is or move it into funds. What do you recommend?

-- Susan Johnson, St. Paul, Minnesota

The first thing I recommend is that you reward your parents' generosity by really hitting those books and shooting for a 4.0 grade point average. They've not only given you a nice head start in life with a college education -- they've also given you a leg up on building a nest egg that can provide financial security later in life. You're obviously insightful enough to appreciate that without me telling you, however, since you were also smart enough to ask me for some advice about what to do with your ten grand windfall.

Okay, now on to the financial portion of my advice. First thing I recommend on the investment front is that you stop trying to guess which way the economy or the market is heading over the short-term. It's futile. Just look at the conflicting signs we've gotten recently. Just a couple of weeks ago, economic indicators suggested the economy was heading for a robust recovery, so robust in fact that many investors were worried that Fed chairman Alan "Span the Man" Greenspan would begin raising interest rates to cool things off again.

But no sooner was everyone convinced that the Fed was about to start jacking up rates again than factory orders came in below expectations and the latest jobs data suggested perhaps the turnaround wasn't yet quite as robust as we thought. Meanwhile, the market's basically been meandering up and down going, well, nowhere really, because no one really has a fix on when the economy will start humming again and when corporate profits will take off.

So forget about trying to figure out whether you're better off investing now or holding off till later. The best time to invest your money is when you have it. As they say (and I'm not sure who "they" is in this case, except they've said it many times), it's time in the market, not timing the market that counts. Which is to say that the real road to wealth is to own stocks for a long time and participate in the growing economy. Jumping in and out of the is a gambling strategy, which makes you more like the guy playing the roulette wheel in Vegas than a disciplined investor. Better to learn that distinction now while you're young than learn it later in life after incurring lots of trading losses.

Now let's move on to what kind of funds you should put your ten large into. Here, I advocate the KISS strategy: keep it short and simple. The first thing you've got to do is figure out how much of your money should go into stock funds and how much into bond funds.

For someone your age who presumably won't have to touch this stash for at least ten years, preferably longer, you should have most of your money in stock funds. The exact percentage can vary, but it's probably somewhere in the neighborhood of 70 to 90 percent, depending on how much it bothers you to see the value of your investments bounce around in the short-term. For more on how to arrive at a mix that fits your situation, check out our Asset Allocator calculator.

Once you've got your mix down, you can start figuring out which stock and bond funds you should own to put that mix into action. Again, I like keeping things simple. I believe you can get pretty much everything you need into two funds.

For stock exposure, you could go with a fund that tracks a broad market stock index like the Wilshire 5000, which includes virtually every publicly-traded stock in the U.S. One fund that's pegged to this index is the Vanguard Total Stock Market Index fund. For your bond exposure, you could go with a bond fund that tracks a broad bond market index like the Lehman Bros. Aggregate Bond index, which essentially tracks the entire U.S. bond market. A fund that tracks this index is the Vanguard Total Bond Market Index fund. (I don't want to appear to be shilling for Vanguard here, but the company really is the king of indexers for individual investors.)

By owning just these two funds, you pretty much own the entire U.S. stock market and U.S. bond market -- that means both large and small stocks, growth and value stocks, and virtually the entire spectrum of bonds (although not municipal bonds, which are generally a better bet only as you get into higher tax brackets anyway.)

Now, that's not to say you couldn't add some other funds. Using your broad index funds as a core, you could add, say, a fund that adds international stocks so your portfolio isn't dependent solely on the fortunes of the U.S. economy. And you could also branch out into other types of domestic funds, adding shares of some whose managers specialize in certain types of stocks -- small undervalued shares, for example, or shares of stocks with rapidly growing earnings. But that can all wait until your senior year or later, if you get to it at all.

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I'll leave you with one other thought. Before you invest any of your ten grand, why not first do a little research about investing in general and funds in particular. You could start by taking a look at the Basics of Investing and Investing In Mutual Funds lessons in our Money 101 series. And in my completely unbiased, totally objective opinion, I think you might also profit from taking a look at my own opus on investment advice, Investing For the Financially Challenged.

But, whatever you do and whatever sources you consult, don't make the mistake of trying to time your entry into the market. Decide on a portfolio mix, pick a few funds and take the plunge. I'm not saying the value of your ten grand won't bounce around a bit. In fact, it will likely experience some gut-wrenching drops over the ensuing years. But unless you think the U.S. economy will shrink over the next 10 to 20 years, then the odds are high that your stash will grow -- and you'll be glad you had the foresight even as a tender undergraduate to put your money to work in the market.

Walter Updegrave is the author of Investing for the Financially Challenged and can be seen regularly Monday mornings at 8:40 am on CNNfn.