Most of us realize that it's a great idea to get your kids into investing as early as possible. That's how Fool co-founders David and Tom Gardner began, after all. (Read "Growing Up Gardner.") We've tackled this topic many times in Fooldom, such as in these pieces:

And we've got a robust nook for Teens and Their Money, too.

There are many ways to pique kids' interest in investments. One is by zeroing in on the companies that already interest them, such as Disney (NYSE:DIS), with its movies and theme parks and all, and Apple (NASDAQ:AAPL), which may have made the computer they turn on every day or the iPod they listen to. Another is to find connections between investments you find compelling and your kids.

In our online Fool Community, ZuzuFool offered a useful example:

I have a three-year-old son. As a three-year-old, he is obsessed with (fascinated by, frightened of, etc.) spiders, and of course -- Spiderman.

Now my son has figured out that when I get certain magazines in the mail (of the financial ilk), he can find the ads for S&P 500 SPDRs (AMEX:SPY). We have all seen the ubiquitous green spider in the clever advertisements for SPY. My son's favorite color is yellow - so he prefers the S&P 500 Mid-cap Spiders (AMEX:MDY) ad. We have a few of these cut out and pasted on his wall.

Now my son does not yet have an investment account (well, technically he does with the 529 account), but there is no doubt in my mind that when he does, there will be a place in it for mid-cap spiders.

There was a lot of chagrin aimed at the cigarette companies for marketing characters like [Reynolds American's (NYSE:RAI)] Joe Camel to children. I give three cheers to Standard and Poor's for marketing investment vehicles to children.

The Spiders alluded to are exchange-traded funds (ETFs), which are essentially stock-like index funds. Buy one or more shares of Spiders, and you'll instantly have about 3% of that money invested in General Electric (NYSE:GE), about 1% in Wal-Mart (NYSE:WMT), and 94% in 498 other firms. Buy a share of Mid-cap Spiders, and you'll be a part-owner of Expeditors International of Washington and Cognizant Technology Solutions (NASDAQ:CTSH), among many others.

Spiders and other ETFs make a lot of sense for some investors. Learn much more about them in our ETF Center. It features info on how ETFs stack up against mutual funds, how to develop an investment strategy with ETFs, pitfalls to avoid, and how to avoid ETF impostors.

These articles may also be of interest:

You can find out more about family investing by taking a free look at our Motley Fool GreenLight newsletter service . Gather the family around the computer and sign up for a free 30-day trial today!

Disney is a Motley Fool Stock Advisor recommendation and Wal-Mart is a Motley Fool Inside Value pick.

Longtime Fool contributor Selena Maranjian owns shares of Wal-Mart. The Motley Fool has a family-friendly disclosure policy.