This is part of the America's Future series airing on FOX News Channel, looking at the challenges facing the country in the 21st century.

LOS ANGELES — Teens choose to drop out of high school for a variety of reasons, and these days, the large numbers of students making that choice is alarming many educators.

The educators often hear stories like that of Tanya Stoddard, 37, who dropped out of high school in her senior year.

"Right when it happened I felt completely brokenhearted, like a total failure," Stoddard said. "I just felt incomplete."

A series of family problems, health and economic woes made school seem irrelevant, Stoddard said, so she left school before graduating and supported herself with a series of odd jobs.

In California, educators are using new tracking data called the Statewide Student Identifier System to get a better handle on the dropout rate and where kids end up going. Recently, they were surprised to learn the figures were twice what they originally thought.

"When you look at the dropout figures for California, the 24.2 percent figure is totally unacceptable," said Jack O'Connell, the state's superintendent of public instruction.

That figure is based on the state's new formula for calculating dropout rates. The method for tracking dropouts varies around the country, and other estimates often are much lower. But any way you count them, the dropout numbers can translate to social problems.

"We know that dropouts are much more likely to engage in crime. They're much more likely to be unemployed. They're much more likely to be dependent on welfare," said Russell Rumberger, who heads up the California Dropout Research Project at the University of California at Santa Barbara. "So they suffer individually as well as society suffering in terms of absorbing all the costs that these dropouts generate."

His research shows California dropouts from a single year, the class of 2009 for instance, could cost state and federal governments nearly $50 billion dollars over the course of their lives in lost wages, social programs, incarceration and health care costs.

But some students are able to get back on the right track and become role models.

It took Stoddard just two years to realize the lack of a high school diploma would hold her back from any kind of real success in life, so she went back to school, earned undergraduate and graduate college degrees and now is planning to pursue a doctorate in education.

"If your intention is to drop out, pleased don't," she said. "I can't tell you the heartache that comes with dropping out. Even when you say it doesn't matter, it really does. It will stop you from being able to achieve."

O'Connell said one solution, particularly in California, is to invest more in education.

"The state of California today, if you look at dollars per student, we rank 46th out of all 50 states in terms of dollars per student," he said. "That's abysmal."

Aside from money, experts say the focus should be teacher accountability, which often creates problems with powerful unions. Also important are community involvement and a stronger relationship between school and student, so kids view learning as a priority and not a problem.