A growing number of public universities are requiring that students have health insurance (search) before they step into the classroom, a move aimed at saving the uninsured from huge bills and college hospitals from getting stuck with the cost.

Most public universities still leave the decision up to students, who can buy into a school's student health care plan or obtain their own insurance. However, surveys from insurers and schools indicate that anywhere from 10 percent to 30 percent do not have insurance. Most are still covered under their parents' plans.

College officials also are finding that some students are forced to drop out when faced with the medical expenses.

"What makes it a tough decision is the potential added costs," said Jim Mitchell, director of student health services at Montana State University (search), which has required insurance for nearly 20 years. "But there's compelling reasons to do it."

More schools have started mandating the coverage in the past four years. Hospitals no longer absorb the costs because of increasing health care expenses.

The University of Connecticut, Ohio State University (search) and all 10 schools within the University of California system now require health insurance. The University of Utah is looking into it.

Others, including Old Dominion, Kent State University and South Dakota's board of regents, have decided against the idea.

Costs vary from campus to campus — undergraduates at UCLA paid $558 for a full year; the price is $1,211 this year at the University of Toledo, where insurance is required.

Yet, some schools have resisted mandatory coverage, fearing extra costs will push students to other colleges. Still, others worry students already are burdened with huge loans and rising tuition.

"We may be pricing students out of college," said Alex Wright, president of the student government at Bowling Green State University.

The costs to uninsured students can be staggering when they're hospitalized.

For example, a student at Old Dominion University, in Norfolk, Va., had $100,000 in medical bills stemming from injuries in a car accident, said Jenny Foss, director of student health services.

"Students can take care of their car repairs, but they may not be able to take care of their injuries," she said.

In extreme cases, the student is forced to declare bankruptcy.

Allowing students to decide whether they want health insurance can dilute a school's health plan when few buy into it. Often, Foss said, it's mainly students with health problems who purchase coverage, driving up the number of claims and costs.

Old Dominion discontinued its health insurance plan a year ago — only 400 of its 20,000 students were using it. That's despite a school survey that showed about 4,000 students had no health coverage.

Glenn Egelman, director of student health at Bowling Green, noted that something as common as an appendicitis could result in a big medical bill.

"It can happen to anyone, at any time, and it can definitely happen to young people," he said. "We see students who have to leave school because of something that can't be predicted."

Students without coverage also think they can get what they need at campus health centers, which often offer free, but limited, care.

"It's a safety net, but it's a net with a lot of holes in it," Egelman said.

Nearly all private colleges make health coverage mandatory, compared with about 25 percent of public colleges, said Stephen Beckley, who runs a Colorado-based consulting firm that assists schools with student health programs.

Unpaid medical bills were a problem at Ohio State's medical center before the school changed its policy three years ago. In one year, the school found uninsured students owed $600,000, said Ted Grace, director of student health services.

"It made it very easy to make that decision," he said.