HARRISBURG, Pa. — Bombs often exploded a half-mile away from Tech. Sgt. Christopher Swisher's tent at Bagram Airfield in Afghanistan.

Yet Swisher said the bombs weren't the toughest challenge he faced in completing his coursework for his Central Penn College degree during his deployment. He cited two bigger obstacles: His textbook didn't arrive until 10 days after the class began, and he had only intermittent Internet access.

If it wasn't the mice chewing through cabling that provided Internet service to his tent, he said, it was the military's computer system not being able to download the giant PowerPoint files from his professor. He ended up paying $70 a month to get more reliable service from a government contractor.

"I basically was on the brink of unraveling," he said.

Swisher, 43, a member of the Pennsylvania National Guard, returned to his home in Lancaster in December. He graduated summa cum laude from the East Pennsboro Township college five days later.

"It was a miracle that I even was able to finish," he said.

Colleges and universities offering distance education are seeing a growing number of soldiers taking classes, said Barmak Nassirian, the associate executive director of the American Association of Collegiate Registrars and Admissions Officers, which represents 2,300 institutions.

This phenomenon is fueled, in part, by the military's enhanced educational benefits. The post-9/11 GI Bill, which became available this fall, allows veterans or active military members to earn degrees at public and some private colleges at little to no cost.

As of last week, 385,000 veterans and active military members had applied for this benefit, and 185,000 of them or their dependents are enrolled in post-secondary schools.

Penn State University's online World Campus has 398 active military members enrolled, and 35 are stationed overseas.

The military offers generous educational benefits to encourage soldiers to advance their schooling, said 1st Lt. Israel Miller, an education support branch chief for the Pennsylvania National Guard. Not only does it make them better critical thinkers and decision makers, but it helps the soldiers earn points to advance their military careers or prepares them for civilian careers, he said.

"We want to educate our troops as much as possible," Miller said.

The military also urges deployed troops to consider online courses for another reason, said Ginny Newman, Penn State's assistant director of military education.

"It's a very positive and constructive use of down time as opposed to other activities that would not be as productive," she said.

Swisher agreed boredom crops up, even in a war zone.

"At night, you either got the gym or ... the entertainment, like they have salsa night and country night. ... But if you are not doing that, you're not doing anything," he said.

Besides, even though he shared a tent with 50 soldiers, he found it easier to concentrate on his studies in Afghanistan than he would have if he had been with his two children and his wife at home, with "MacGyver" reruns playing on TV.

"When there's that many people in a tent, nobody talks loud. ... It was a great place to study," Swisher said.

While in Afghanistan, he did research for a paper on a solution to labor-management issues at Verizon, where he works in the civilian world as a technician. He took his final business course, Foundations of Financial Management.

Swisher said his Marine training that taught him to adapt, overcome and improvise came in handy during the six years it took to complete his degree in business administration/management (his education was interrupted by two prior deployments). He hopes the degree will increase his marketability in the military or in the international job market.

Army Spc. Ryan Morrison of Harrisburg, Pa., who is in the midst of a yearlong deployment in Iraq, is learning all about those coping skills now.

Morrison, 20, of Harrisburg, enrolled in Penn State's World Campus recently and started his studies with Introduction to Criminal Justice.

The Bishop McDevitt High School graduate said in an e-mail that he started out taking only one course because of his busy schedule. The biggest challenges he has encountered so far are keeping up with schoolwork in between his two- and three-day missions and, like Swisher said, intermittent Internet access.

"I try to cram as much as I can while on radio watch," he said. That duty entails listening to radios and keeping in contact with other units for long stretches of time.

"What I can't get done there I do after my 12-hour work shift in my 2 man chu," which he described as a shipping container that has a door cut in it and houses two to four soldiers.

Morrison said other soldiers who have taken online courses encourage him to stick with it. They tell him "to complete my classes and to try and not get behind on my school work and that to finish my classes because I won't regret it later in life," he said.

Many military students get frustrated by the challenges — technical and otherwise — that arise while deployed, and they drop courses.

Kaye Keith, an administrative support coordinator in the Penn State registrar's office, said she tries to warn deploying students about those drawbacks, but that doesn't deter some from enrolling in the university's online courses.

"Many times, they say to me, 'I don't want to stop school altogether. I want to continue and keep that link and be part of Penn State while I'm over there,' " Keith said.

For faculty and staff, having students living halfway around the world in a war zone can mean doing things they wouldn't typically do for on-campus students.

Instructors of Harrisburg Area Community College's online courses send proctored exams overseas, said Adam Walter, HACC's coordinator for military and veterans affairs.

Faculty and staff have to make themselves available at odd hours to communicate with their military students because of the time differences, Newman said. Sometimes they have to advocate for students at the admissions office or student affairs. Sometimes, faculty have to bend due dates for class assignments.

In Swisher's case, Central Penn College business administration professor Kathy Hepner said she had to adapt her instruction since he couldn't access the online materials provided to other students in the class.

But she didn't mind for the same reasons echoed by officials at other schools.

"I would go and do whatever I can do for somebody who was deployed over there because it's amazing what they do for us," Hepner said.