In addition to cards often offering cash back savings as a percentage of purchases, look for cards with special offers throughout the year, Harzog says. Right now, Chase Freedom is offering 5 percent cash back on purchases at Kohl's, theme parks and gas stations, she says.
The offer lasts until the end of September, but the card offers different deals every quarter, according to its website.
The Blue Cash Preferred card by American Express offers 6 percent cash back on grocery purchases up to $6,000 per year. That's $360, which adds up to $3,600 in 10 years. Parents can also check out both Upromise- and Fidelity Investments-affiliated cards, where cash back is directly deposited into a 529 plan.
Parents shouldn't underestimate the total value of these programs. "My friends think I'm crazy when I look for different ways to use Upromise, but a buck here, a buck there adds up," Yager says.
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