Courtesy of Olivia Ragni Olivia Ragni, 19, scrubs an elephant in Thailand. During her gap year, Ragni also volunteered at a hospital in India and studied Spanish in Guatemala.

This summer, Monika Lutz's life took an unusual turn. Instead of heading off to college, the high school graduate packed her bags for a Bengali jungle. Lutz, like a growing number of other young Americans, is taking a year off. Gap years are quite common in Britain and Australia, but they are just beginning to catch on in the U.S. Lutz, who grew up in Boulder, Colo., has put together a 14-month schedule that includes helping deliver solar power to impoverished communities in India and interning for a fashion designer in Shanghai  experiences that are worlds away from the stuffy lecture halls and beer-stained frat houses that await many of her peers. "I could not be happier," she says.

No one tracks the number of U.S. students who decide to take gap years, but many high school guidance counselors and college admissions officers say the option is becoming more popular. Harvard, which has long encouraged its incoming first-years to defer matriculation, has seen a 33% jump in the past decade in the number of students taking gap years. MIT's deferments have doubled in the past year. And Princeton formalized the trend in 2009 by funding gap-year adventures for 20 incoming first-years annually. The school's goal is to extend this offer to about 100 students per class. (See pictures of the college dorm's evolution.)

Meanwhile, a cottage industry of gap-year programs and consultants has sprouted in the U.S. Tom Griffiths, founder of GapYear.com a site that serves as a clearinghouse for gap-year programs, says that five years ago, perhaps 1% of his Web traffic originated in the U.S. Now, that figure is 10%. The number of Americans taking gap years through Projects Abroad, a U.K. company that coordinates volunteer programs around the world, has nearly quadrupled since 2005. The organization just launched Global Gap, its first effort marketed specifically to Americans; the 27-week curriculum features service projects in South Africa, Peru, India and Thailand.

Like a year of college, these adventures can be expensive. The price tag for Global Gap is $30,000. Thinking Beyond Borders, a highly respected, eight-month program that parachutes students into third-world communities, costs $39,000. Yes, it's certainly possible for students to pursue meaningful volunteer work on a smaller budget. But unless kids stay at home and get a paying job nearby, families will likely incur significant expense. The increase in interest suggests that at least some families are willing. "There are now more structured opportunities for students to take gap years," says David Hawkins, the director of public policy and research for the National Association for College Admission Counseling. "That doesn't happen unless there's a market to sustain it." (See TIME's special report on paying for college.)

Why are students attracted to the gap-year concept? According to new survey data from Karl Haigler and Rae Nelson, education-policy experts and co-authors of The Gap-Year Advantage, the most common reason cited for deferring college is to avoid burnout. "I felt like I was focused on college as a means to an end," says Kelsi Morgan, an incoming Middlebury College freshman who spent last year feeding llamas at a North Dakota monastery, interning for a judge in Tulsa, Okla., and teaching English at an orphanage in the Dominican Republic. The hope is that after a year out of the classroom, students will enter college more energized, focused and mature. That can be an advantage for colleges too. Robert Clagett, dean of admissions at Middlebury, did some number-crunching a few years ago and found that a single gap semester was the strongest predictor of academic success at his school.

Most experts recommend securing a spot in college before taking a gap year and warn against using the time off to pad your résumé. "Most admissions folks can see right through that," says Jim Jump, the academic dean of St. Christopher's School in Richmond, Va. But for students like Lutz, who, after getting rejected from five Ivies, decided to take time off, a gap year can help reprioritize and focus interests. Lutz now plans to apply mostly to non-Ivies that have strong marketing programs. "This experience has really opened my eyes to the opportunities the world has to offer," she says. (See the 10 best college presidents.)

But at least one education expert doesn't want schools spreading the gap-year message as if it were gospel. In a study that followed 11,000 members of the high school class of 1992 for eight years after graduation, Stefanie DeLuca, a sociology professor at Johns Hopkins University, found that, all things being equal, those who delayed college by a year were 64% less likely to complete a bachelor's degree than those who enrolled immediately after high school. DeLuca did not pinpoint whether these students voluntarily started college late, but at the very least, her work indicates that taking a gap year doesn't guarantee success. "I'm not going to say that time off does not have benefits," says DeLuca. "But I think we should be tempered in our enthusiasm." (Comment on this story.)

No one's gap-year enthusiasm was more tempered than Olivia Ragni's. In the spring of 2009, the high schooler from Arkadelphia, Ark., inadvertently missed the deadline to secure her spot at Rice University that fall and was told she would have to wait a year to enroll. "I was really down," says Ragni, who still cries when recalling the embarrassment of informing her classmates of the unintended deferment. But through two experiential-learning organizations, she spent the year volunteering in a hospital in India, taking intensive Spanish while hiking volcanoes in Guatemala and working at an elephant camp in Thailand. "I gained confidence and independence," says Ragni, who has just arrived in Houston to start her first term at Rice. "It was the best experience of my life." The tears have dried up. Consider it a lucky break.

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