By Melissa Preddy
The Detroit News

Now that the school year's over, many teens will clock more hours at part-time jobs. If that's you, then consider allocating some of your wages to retirement savings.

Retirement savings? What 16-year-old in her right mind would want to give up the right to touch a portion of her hard-earned income for the next 43 years?

A savvy 16-year-old, that's who.

Consider these two contrasting scenarios from the Department of Labor Web site. Similar examples have been trotted out in personal finance tomes in recent years, to the chagrin of plenty of 40- and 50-year-olds who wish they had read the same thing back in the '70s between shifts at McDonald's:

• Starting at age 20, if you put $1,000 a year into an IRA for 11 years and earn 7 percent annual returns, your account will be worth $168,514 at age 65 - even if you never save another dime past age 30.

• If you don't start until age 30, and save the same $1,000 a year for the next 35 years, you will have deposited three times as much money, but your account will grow to only $147,913 by age 65.

This is not to imply that $1,000 a year will provide an adequate retirement fund, but it shows that if you save early, you'll have more room in the budget for fun stuff when you hit those expensive first-time-homeowner, first-time-parent years.

Not every teenage summer worker will be able to eke out $1,000 in savings. But even a seemingly tiny amount, left to ferment for 30 or 40 years, can translate into formidable purchasing power.

Save $25 a week for 16 weeks in a Roth IRA (where withdrawals will be tax-free) and earn 7 percent interest for the next 43 years. Presto! At age 591/2 , when you can withdraw the money free of income tax and penalties, that $400 will grow into more than $8,000.

Roth IRAs may be opened by anyone, of any age, as long as they earn less than the income thresholds ($110,000 for single filers, $160,000 for married couples filing jointly) and have earned income equal to at least the amount of the Roth contribution.

You don't need a lot to get started - no-load mutual fund companies make opening an IRA as easy as starting a checking account. Shop around for fees and other fund costs, remembering that while a 1 percent expense ratio sounds low, it will have an adverse long-term effect on your investment's performance. The Securities and Exchange Commission offers an online mutual fund fee calculator at www.sec.gov.