When it comes to financial literacy, you're never really done learning.
Studies have painted a grim picture about how poorly educated Americans are when it comes to managing our money. Nearly two-thirds of students aged 15 to 18 scored below 70 percent in the National Financial Educators Council financial literacy test, administered to 1,309 people during 2012 and 2013.
Adults haven't fared any better. Asked five multiple-choice questions about topics like interest calculations, mortgage payments and investments, just 39 percent of the 25,509 adults answered at least four correctly, according to a 2012 survey from the FINRA Investor Education Foundation. That's down from 42 percent in 2009. (See chart below for a state-by-state analysis.)
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Financial literacy educators say there's a way to buck the trend, and it isn't all about starting earlier. "We're falling into a very common trap: We're too focused on high school," said Ted Beck, president and chief executive of the National Endowment for Financial Education.
Historically, that's where the bulk of financial literacy programs have targeted their efforts. But studies have found that the retention rate on financial lessons learned is two years at best, said Beck—a track record supported by such financial literacy test results. A comprehensive personal finance education in high school may not fully prepare someone years later to buy a home, understand his workplace benefits or save for retirement, especially with a rapidly shifting array of financial products and tools in the mix.
"The decay factor in that knowledge gathering is very high," Beck said. "You need boosters."
Even older adults, who have arguably learned something about personal finances by managing their own, could stand a refresher. "The school of hard knocks is certainly a good way to learn," said Gerri Walsh, president of the FINRA Investor Education Foundation. "[Older adults] appear to have stronger levels of financial knowledge and better behaviors."
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FINRA found respondents age 55-plus got a mean 3.3 answers out of 5 correct versus 2.9 for those in the 35-to-54 bracket and 2.3 for those age 18 to 34. "The reality is among those 55 and older; they're still getting a lot wrong," she said.
To that end, in recent years financial literacy programs, debt counselors, financial institutions and employers have made new efforts to help adults improve their money-management skills. In its 2013 Workplace Benefits Report, Bank of America Merrill Lynch found that 70 percent of the more than 1,000 employers it surveyed now offer workers one-on-one access to financial advisors, up from 56 percent a year earlier.
Still, the idea of a continuing financial education can go against the grain for many consumers. "There is a gap between how we perceive ourselves and how we test out," said Walsh. "We think we're good at managing our money. But when you start slicing and dicing that data, you see there are people who give themselves high marks…but overdraw their checking account or carry a balance on their credit card."
Pamela Thornton of Yeadon, Penn., wasn't sure she needed a refresher on budgeting and saving when a neighbor asked her to come along to a financial literacy workshop through nonprofit Clarifi. "I thought I was already financially situated," said Thornton, 52.
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The workshop turned out to be a game-changer, helping Thornton reassess the bank accounts she was using and find new ways to kick her savings into high gear. Opening her own bakery, something she'd thought out of reach, suddenly seemed doable. "I was so overwhelmed with what they had taught me," she said. Pound Cake Heaven now has two locations, and Thornton plans to take more classes to better run the business.
State-by-state financial literacy scores
|State||% who got 4-5<br> answers correct||Mean of correct<br> answers||Mean of "I don't<br> know" answers|
|District of Columbia||43%||2.95||1.07|
If there's a bright spot in Americans' dismal financial literacy scores, it's that more people seem willing to admit there are some gaps in their education. Last year 40 percent of adults graded their personal finance knowledge a C, D or F, according to a Harris Interactive survey of 2,037 adults for the National Foundation for Credit Counseling and the Network Branded Prepaid Card Association. That's up from 35 percent in 2010.
"What that tells me is, they know they don't know," said Gail Cunningham, a spokesperson for the NFCC.
There wasn't a financial literacy course at her high school, so when Rebecca Harkless graduated from college, she decided to seek out one-on-one coaching sessions at social services agency Gateway. The aim: to help her set aside more of her income and make smarter budgeting decisions so she can be financially independent. "I have income," said the 24-year-old Birmingham, Ala., native, "but it's not just income you need. That's something that I've really taken from this. When it comes time to make those big decisions, I won't be uninformed."
Boosting your knowledge as an adult does require more effort than making it to class on time as a high school student, but technology has made it easier for consumers to track down basic tools and to take online workshops if their schedule is crunched, said Beck. "Once you've got a basic sense, then you can start to gather information from unbiased sources when you're starting to think about financial decisions," he said.
(Read more: Education is key to retirement planning)
There's always something new to learn, even if you feel fully versed in a topic from prior experience, said Cunningham. "Personal finance becomes more complex every day," she said. "There are always new tools, new apps, new products. In my life, we've bought and sold seven houses, but it's still a new day every time we do it."
There's yet another pressing reason to make sure you're keeping up with your financial education. Despite the range of financial literacy initiatives targeting children and teenagers, 33 percent of consumers in a recent survey told the NFCC that they primarily learned personal finance from their parents.
"What's going to happen if Mom or Dad doesn't have good personal finance skills?" said Cunningham. "Financial education really can be a twofer. What you learn, you can teach your kids—and break the cycle."
—By CNBC's Kelli B. Grant. Follow her on Twitter @Kelligrant and on Google.
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