NEWINGTON, Conn. -- Back-to-school shopping can mean big bucks for retailers, and yet another expense for parents, especially when it comes to shoes.

Some parents say their wallets are emptying just as quickly as children outgrow shoes. According to a newly released study commissioned by the National Retail Federation, families in the northeast will spend an average $456 on back-to-school items this year.

Channel 3's Denise D'Ascenzo explained how finding the right fit can make a significant difference.

Doug Rich, who works for a shoe store called Footprints, has been fitting shoes on children and adults for more than 20 years.

"The biggest problem in the shoe business is the sizes don't run true to size," Rich explained. "Every child's foot is very unique and certain styles will fit certain feet better than others."

He said children's feet can range a little in size, by about a sixth of an inch.

"You'll find that, usually, if you're right-handed, your left foot is bigger in 90 percent of the population," he said.

Rich suggests buying a size for the bigger foot when the two feet sizes differ. He also said it's important to look at the outline of your child's foot to match your child with the right shoe shape.

For parents who try to stretch their dollar by buying larger shoe sizes, Rich warns, "Some parents like the shoes to fit longer because they think they'll get more time in them, but they don't realize it's a lousy fit. What happens is the arch moves too far down the foot."

How fast do children's feet grow?

• Kids 6 to 10: every two to three months
• Teens: every three to four months
• By age 16: the size may change only every six months or more

Other fast fitting facts for footwear include:

• Make sure the shoe fits comfortably around the ankle
• Have the child wear the socks he or she will be wearing with that particular shoe
• When buying sneakers, always size up a half size

Rich said sneakers tend to run a half size smaller and that rule even applies to adults.

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