As the first in her immigrant family to attend college, Lucia DiPoi said she had few clues about how to finance her college education. So when financial aid and low-interest government loans did not stretch far enough DiPoi applied for $ 49,000 in private loans. "How bad could it be" She recalls thinking. Apparently it can get pretty bad. The rising costs of university tuition in the U. S. are pushing many young American like DiPoi toward private lenders with high, fluctuating interest rates. As a result, students are taking on large debts that will stay with them for years into their careers. Every American student has access to federal education loans. They are issued by the government at fixed, low interest rates. But since students often need more money than the federal loans provide, they are increasingly turning to private lenders. These lenders will happily loan out lots of money, but sometimes at changing interest rates much higher than those of federal loans. When DiPoi graduated from Tufts University in Boston, her debt had reaches $ 65,000 with interest. She owed an additional $19,000 in federal loans. Every month she has to pay $ 900 back. As a result, DiPoi, now 24, has had to give up her dream of working in a refugee camp overseas. The pay, she said, "would have been enough for me but not for Sallie Mac, the nation’s largest student lender." New York State Attorney General Andrew M. Cuomo has called private loans the Wild West of lending. Private lending has become the fastest-growing sector of the student finance market, more than tripling over five years to $17.3 billion in the 2005 ～ 2006 school year, according to the College Board. Unlike federal loans, whose interest rates are capped by law-- now at 6.8 percent--these loans carry variable rates that can reach 20 percent, like those of credit cards. Many private loan agreements do not allow students to reduce the principal by paying extra amount each month unless they are paying off the entire loan. "It’s a huge problem," said Barmak Nassirian, associate executive director of the American Association of Collegiate Registrars and Admissions Officers. "When a student signs the paper for these loans, they are basically signing their life away," Nassirian said. "We’re putting these kids into debt for life." But Tom Joyce, a spokesman for Sallie Mac said the company’s average interest rate on private student loans was just over 10 percent. The average young person also has little or no credit history. "What would the credit card interest rate be for that borrower-- 24, 25 percent" Joyce asked. "Our goal is to make it possible for students to graduate.\ "Fluctuating" in the third paragraph means that the interest rate is ______.