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CAN'T BUY ME LOVE, from left: Patrick Dempsey, Amanda Peterson, 1987.
Your teens summer earnings can't buy love, but they can buy a bit of retirement security.
Buena Vista Pictures—Courtesy Everett Collection

In my last column, I extolled the virtues of opening—and perhaps even contributing to—a Roth IRA for a working teenager. In short, a little bit of money saved now can make a big difference over a long time, and give your child a nice cushion upon which to build a solid nest egg.

Besides underscoring the importance of saving for retirement early and regularly, opening a Roth IRA can help your child become a savvy investor (a skill many people learn the hard way).

Here's how:

Make the Initial Contribution

Your child needs to earn money if he or you are going to contribute to an IRA on his behalf. For the 2014 tax year, the limit for a Roth IRA contribution for those under age 50 is the lesser of the worker’s earnings, or $5,500.

The deadline for making the contribution is April 15, 2015. But you can start sooner, even if your teen hasn’t yet earned the money on which you will be basing the IRA contribution. (If the kid doesn’t earn enough to justify your contributions, you can withdraw the excess with relatively little in the way of paperwork or penalties.)

For a minor child, you will have to open a “custodial” Roth IRA on her behalf, using her Social Security number. Not every brokerage or mutual fund company that will open a Roth IRA for an adult will do so for a minor, but many of the larger ones will, including Vanguard, Schwab, and TD Ameritrade.

As the custodian, you make the decisions on investment choices—as well as decisions on if, why, and when the money might be withdrawn—until she reaches “adulthood,” defined by age (usually between 18 and 21, depending on your state of residence). Once she ages out, the account will then need to be re-registered in her name.

Depending on which provider you choose, you may be able to make systematic, automated contributions to the IRA (for example, $200 per month) from a checking or savings account. To encourage your teen to participate, you might offer to match every dollar he puts in.

Have the "Risk vs. Reward" Talk

How an adult should invest an IRA depends upon the person's goals and risk tolerance—the same is true for a teen. You can help set those parameters by pointing out to your child that, since he's unlikely to retire until his 60s this is likely to be a decades-long investment, and enduring short-term downturns is the price for enjoying higher potential long-term gains.

You might also show him the difference between depositing $1,000 now and earning, say, 3% annually vs. 7% annually over the next 50 years—that is, a balance of $4,400 vs. a balance of $29,600. Ask your child: Which would you rather?

No doubt, your kid will choose the bigger number.

But you also want this to be a lesson in the risks involved in investing. You might talk about what a severe one-year decline of 40% or more might do to his investment and explain that bigger drops are more likely in investments that have the potential for bigger growth. Now how do you feel about that 7%?

Some teenagers will be perfectly fine accepting the risk. Others may be more skittish.

You also might explain that there are options that will not decline in value at all—such as CDs and money market accounts. But should he choose those safer options, he'll be trading off high reward for that benefit of low risk. In fact, while his money will grow, it will likely not keep up with the rate at which prices grow ("inflation," in adult terms). So his money will actually be worth less by the time he's ready to retire.

Some risk, therefore, will likely be necessary in order to grow his money in a meaningful way.

Choose Investments Together

Assuming he can tolerate some fluctuation, a stock-based mutual fund is probably the most appropriate and profitable strategy—especially since a fund can theoretically offer him a ownership in hundreds of different securities even though he may only be investing a few thousand dollars. You might explain that this diversification protects against some of the risks of decline since some stocks will rise when others fall.

A particularly-suitable option might be a “target date” or “life cycle” fund. These offerings are geared toward a specific year in the future—for instance, one near the time at which your child might retire.

Target date funds are usually a portfolio comprised of several different funds. The portfolio allocation starts out fairly aggressive, with a majority of the money invested in stock-based funds, and much smaller portion in bond funds or money market accounts.

As time goes by—and your child’s prospective retirement draws nearer—the allocation of the overall fund gradually becomes more conservative.

The value of the account can still rise and fall in the years nearing retirement, but with likely less volatility than what could be experienced in the early years.

One low-cost example of this type of investment is the Vanguard Retirement 2060 Fund (VTTSX).

Of course, if you choose a brokerage account for your child’s Roth IRA, you have the option of purchasing shares in a company that might be of particular interest to your kid. Choosing a company that is familiar to your child may not only inspire her to watch the stock and learn more about it, but eventually profit from the money she is spending on “her” company’s products.

If you're going to go this route, you should include a discussion on the increased volatility (for better or worse) of owning one or two stocks, rather than the diversification offered by the aforementioned mutual fund.

Kevin McKinley is a financial planner and owner of McKinley Money LLC, a registered investment advisor in Eau Claire, Wisconsin. He’s also the author of Make Your Kid a Millionaire. His column appears weekly.

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