BOSTON — Nearly all of us have spare change piling up in a jar or piggy bank, or accumulating beneath the couch cushions. But $7,000 worth?

That's how much Clark Pellington's family has collected in coins the past five years. It's a windfall from life's little transactions — change from that cup of coffee bought on the way to work, or a few dimes back from the toll booth clerk.

"I bring home every penny that lands in my pocket," said Pellington, a married 46-year-old financial services professional from Wayne, N.J.

Pellington's 9-year-old son and 5-year-old daughter split the proceeds from the family's coin stash, but don't blow it on toys or candy. Once a month, the kids round up their piggy banks and join Mom and Dad on a trip to a Penny Arcade machine at a local TD Bank branch.

There, they get a penny-for-penny return on their coin exchanges. The money goes into the kids' savings accounts. Each time one of the accounts hits $1,000, they move the cash into certificates of deposit that earn higher interest than savings accounts.

It's a way to feed the kids' college savings funds, and teach a lesson.

"In a few years, I'll teach them the virtues of compound interest," Pellington said. "A lot of parents sock away money for their kids. But if their kids don't learn how to manage money and save, the message doesn't get through."

If you do turn your coins in, don't necessarily expect an even exchange. Usually, it depends on how much you're willing to pay for convenience. Here are some options:

YOUR BANK: Coin exchange policies vary from bank to bank and sometimes from branch to branch. Generally, banks will give you back a full return in bills or a credit to your account if you bring in coins sorted in paper rolls. But the policy may not be so generous if you haven't sorted the coins, or aren't a customer of the bank. So you may want to call or check the bank's Web site before you load up on coins to drop off.

COINSTAR: The nation's biggest coin exchanger is Bellevue, Wash.-based Coinstar, an 18-year-old company whose network of coin-counting machines in grocery stores and other retailers has grown to more than 18,400. Dump coins into the machines and you'll get back a voucher.

But you pay for Coinstar's convenience. The machines charge a processing fee of nearly 9 cents on the dollar.

However, Coinstar has a new initiative offering no-fee coin exchanges — provided you're willing to redeem your money at one of more than a dozen participating national retailers. Some Coinstar machines spit out gift cards that allow you to spend coin-exchange cash at retailers including www.Amazon.com, Lowe's, Old Navy and Starbucks. The site www.coinstar.com features a locator to find a nearby machine.

COINS FOR CHARITY: If you're willing to donate your coins for a good cause, you can use Coinstar and Penny Arcade machines to give to a number of charities. Look for the menu options on the machines that designate charities.