Until recently, Roland Crispin viewed the Persian Gulf like most college students who expect the closest they'll ever get to a war in the Middle East is a course on Alexander the Great's military strategies.

Now Crispin, a senior at the University of Maryland, is one of a growing number of Washington area college students who have had to withdraw from classes to strengthen the military might of Operation Desert Shield. So far, at least 160 local students, members of military reserve units that helped pay their tuition, have had to abandon the classroom. Some will not get credit for academic work completed. Many will not graduate with their classmates.

Pentagon officials said they do not know how many college students nationally have had to drop academic studies for at least six months of active military duty, but they say that about 10 percent of all military reservists receive college tuition benefits and 125,000 reservists have been called to duty.

Many of the dozen college reservists interviewed in the last two weeks said they underestimated the risk involved in taking the benefits. Compounding their reluctance to leave school, several reservists said, is the increasingly visible peace movement on college campuses.

For the first time since the military draft during the Vietnam War, college students are seeing classmates pulled from their studies for military duty.

On almost every campus in the Washington area, and many others around the country, there have been teach-ins reminiscent of those that spurred the anti-war movement during the Vietnam War. Five hundred students turned out Dec. 7 for a teach-in at Georgetown University. A week earlier, thousands of college students rallied in Boston Common in protest of the U.S. military buildup. A George Washington University-based group has contacted 100 colleges and universities across the country for a national student protest march in Washington next month.

"When I first got the call, I was a little shaken," said Crispin, 21, before he left College Park for a Marine base in North Carolina. He packed his books and belongings during an emotional farewell with dozens of undergraduates at Baltimore Hall, where he was a resident assistant. "I'm trying not to think about war. I'm thinking about what I'll do when I get back."

In addition to as much as $1,260 in federal education benefits for each school year, members of the National Guard and military reserves receive generous tuition discounts -- often 50 percent -- from many state schools.

Those tuition benefits lured Kelvin Dickerson, a junior at Howard University, to the Army Reserve. Now Dickerson, 22, expects to be called to duty in January. "I think now I might have made a bad decision," he said.

Adding to his ambivalence, Dickerson said, was the recent spate of campus protests. Howard students have papered the campus with fliers condemning the U.S. presence in the Middle East and held protests critical of the large porportion of blacks among the deployed U.S. troops.

"They say things like the deployment is a form of racial genocide," Dickerson said about the campus protesters. "That just intensifies my conflicts even more. It makes you question why you have on the uniform."

A few days before Thanksgiving, Mark Yeo, a senior accounting major at Pennsylvania State University, was summoned from campus to Camp Lejeune, N.C., where he awaits deployment to the Middle East.

Yeo, 21, had to leave school three weeks before the end of the semester. Only two of his five professors gave him credit for the semester's classes.

"I signed up to do this," the college senior said in a telephone interview after a nighttime weapons firing test at Camp Lejeune. "But I also want to finish school. I was so close to graduating."

Kathy Shepard, a junior at Penn State, said that Yeo's departure has made his friends and classmates "worry more about what is going on in the Middle East," and brought the gravity of the crisis home.

Yeo, who will help haul Marine supplies and troops in the Middle East, said he hopes that the student protests don't spread. "Protesting is the worst thing that could happen," he said. "If the president feels we should be over there, we need to support him."

A majority of college students remain uninvolved in the protests. But since October, the number of new student groups agitating against the U.S. troop buildup has increased by the week, said Mary Beth Maxwell, organizing director of the U.S. Students Association, a national membership organization of student activists and governments.

Almost every Washington area college and university now has an organized group protesting the military buildup, sending anti-war letters to President Bush and planning rallies, teach-ins and marches. Aegis Justice, a newly formed pacifist group based at George Washington University, is trying to form a national communication network among all college groups. To date, it has contacted 100 colleges and universities to coordinate protest activities, said Dwayne Voegeli, one of the group's founders.

Many students pay for the long-distance calls to other groups themselves, according to interviews with the activists. But increasingly, Georgetown and George Washington university activists said, they are being aided by other nonprofit groups, who lend their telephones and facsimile machines.

Chris Moore, a Georgetown University anti-war activist, said many students are critical of the mounting cost of the U.S. presence in the Middle East and fear that education and social programs may be cut as a result. "We're spending $83 million a day. That money has got to come from somewhere," Moore said.

Other political causes, such as the massacre of Chinese students in Tiananmen Square, U.S. support of the Nicaraguan contras and the killings of Jesuit priests in El Salvador, have elicited student outrage, Moore said, but not nearly to the degree of the Persian Gulf crisis.

Not all the college reservists who have been called to active duty are being sent to the Middle East, but nonetheless their lives have been turned upside down. Karen Reschke, a student in George Mason University's school of nursing and a Navy reservist, was pulled out of school in August to bolster the depleted staff at Bethesda Naval Hospital. Most of the regular hospital staff is on a hospital ship in the Persian Gulf.

"I was crushed," Reschke, a Woodbridge resident, said. "I had two years left to get a degree in nursing . . . . Who knows how old I'll be when I finish now."