Every year, Boynton Health Services at the University of Minnesota surveys the state's college students to see how academic performance is affected by lifestyle factors such as stress, lack of sleep and drug use. And each year, director Ed Ehlinger and his staff notice a powerful correlation: students with health insurance get better grades.

Ehlinger can't prove it's cause-and-effect, but he thinks the link is strong enough that colleges should consider requiring health coverage as a way to improve academic achievement. Many schools do, but he estimates that one in six Minnesota college students is uninsured.

The U has required insurance for decades, but recently two other schools -- the University of St. Thomas and Minnesota State University Moorhead -- have begun experiments with mandatory coverage.

The result, playing out at several campuses across the state, is a microcosm of the national health care debate in Washington: Do the benefits of universal health insurance outweigh the costs?

St. Thomas, which dropped mandatory insurance after the paperwork became too much to handle, reinstated the policy in 2007.

"We were very worried about our uninsured rate," said Madonna McDermott, director of the Student Health and Wellness Center. Officials worried about whether students would get medical care when ill -- and how they would pay for it -- without insurance, she said.

St. Thomas likes the results so far: Students are getting more preventive care, more timely services and appropriate tests, McDermott said. In addition, premiums dropped because costs are now spread across a larger, healthier pool of students. That addressed what is known as the "adverse selection'' problem: When insurance is voluntary, the people most likely to buy it are those with health problems, which drives up costs and premiums.

About 10 percent of St. Thomas students use the school-sponsored plan.

Minnesota State University, Moorhead, is in the second year of mandatory insurance, part of a five-year pilot program for the entire Minnesota State Colleges and Universities (MnSCU) system. Moorhead is the only MnSCU school that requires insurance.

Carol Grimm, director of health and wellness at the Moorhead campus, also cited high uninsurance rates -- from 11 to 13 percent -- as a reason for asking to be the test campus. Now, almost 10 percent of students are enrolled in the university's policy.

While the schools worry mainly about their students, Dave Golden, public health and marketing director at Boynton, thinks the general public has a stake, too.

"Education is an investment," he said. "Especially in state schools, where a lot of students are subsidized, we can't have students failing or dropping out because of a lack of health insurance. It's very expensive to lose a student, and not just for the student or the college, but for taxpayers, too."

Although they can't prove a causal link, Ehlinger and Golden say they believe health insurance contributes to better academic performance because students get sick less, miss fewer classes and are less likely to drop out for major health problems.

Nevertheless, the idea triggered a debate on the Moorhead campus when the pilot was launched. Jered Weber, Moorhead's student body president at the time, said some members of student government balked at the cost and worried it might drive students out of college.

Because of their concerns, Moorhead does not require proof of private insurance if students choose not to participate in the school's policy. Many schools, including the U of M and St. Thomas, require written proof of coverage.

Similar concerns crop up across the MnSCU system, according to spokeswoman Melinda Voss. Because 35 percent of the system's students are age 25 or older -- many of them working or married -- Voss said a mandate might not fit.

Despite high interest among Moorhead students, Voss said it's too early to draw larger conclusions from the pilot project.

Grimm, however, says it is never too early to start thinking about health insurance. "You don't need it until you need it," she said, "but when you need it, it's critical."

Megan Hanson is a University of Minnesota journalism student on assignment for the Star Tribune.