Where we lose
A key commonality among countries whose teens scored better than the U.S. is education. New Zealand and Australia, for example, have both developed national financial literacy strategies with mandated education components. "Being proactive has really paid out for their young people," Lusardi said.
China's testing was limited to Shanghai students, a narrow scope Lusardi likened to the U.S. testing only students in Washington, D.C. Still, China and other Asian countries typically rank among the top five for other school subjects—and OECD data showed some positive correlation between financial literacy skills and high performance in mathematics and reading.
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In Shanghai, "the mathematics scores are contributing to a high score in financial literacy," Michael Davidson, head of early childhood education and schools for OECD, told reporters in a webinar on the results.
The U.S. released its National Strategy for Financial Literacy in 2011, but educational components are relegated to the states. Seaton said only four states require high school students take a personal finance course to graduate and another 16 mandate some financial literacy components in classwork.
Even some of those mandated state programs aren't funded, Lusardi said. That leaves it to school districts to figure it out themselves, with varying success.
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Nonprofits and private industry initiatives have stepped in help close the financial literacy gap, but their success is limited by their reach, Seaton said.
"It's difficult to get to the masses with evening and weekend programs," he said. "The major part is going to have to be the public schools, because that's where the kids are."
Davidson said it remains to be seen what kind of educational approach works best—one with a separate personal finance curriculum or one where personal finance issues are interwoven with other subjects such as math and English. Many of the countries surveyed have newly implemented their programs and strategies, so it's premature to expect to see results in the students' test performance.
"The question of, does financial education work or not, is too early to say," Davidson said.