When President Reagan launched an air strike on Libya last April few could have predicted it would create an overcrowding problem at Harvard Summer School.

But fears about terrorism overseas, coupled with a low US dollar exchange rate and increased interest in the University's English as a Second Language program, have inflated student enrollment, forcing officials to scramble for additional housing space.

Approximately 5200 high school, undergraduate and graduate students, an increase of more than 100 over last year, are expected to register Sunday and Monday for the 111th annual Summer School session. About half of the students are requesting on-campus living accomodations.

"The total number of students is higher than in the whole history of the Summer School," says Katherine G. Galaitsis, associate dean for resources. "What we have right now is a situation where every bed is assigned."

To alleviate the housing crunch, the Summer School has already taken over the top floors of the River houses and all of Claverly Hall, both of which they had not planned to do. The top floors are usually very hot and uncomfortable in the summertime, so the School has not used them in the past. Some students may also not receive singles.

While all secondary school students are guaranteed housing, mostly because the University anticipated an increase among this group, Harvard officials say they are still unable to provide on-campus rooms for 30 undergraduates. The School has told these 30 students to find temporary quarters until they can be placed. Further student housing requests will receive the same response.

Braced for Complaints

Administrators admit they were slow to realize that the number of undergraduate Summer School applicants would be higher than ever. They say they are "braced for complaints" from disgruntled undergraduates.

"We can't pack students in as liberally as the College can. We don't have a degree to offer," says Marshall R. Pihl '55, director of the Summer School. "People from outside are not as forgiving."

Each dormitory resident shells out $965 for room and board for the eight week session. The University does not plan to reduce fees for students placed in common rooms. Nor will it pay the temporary housing costs for the 30 students.

High school students will live in the Yard dorms, while older students, of which about 10 percent are currently Harvard undergraduates, will occupy Adams, Dunster, Eliot, Kirkland, Leverett and Mather Houses.

More Foreigners

Of the more than 5200 students, representing 80 nations, approximately 400 will enroll in Harvard's English as a Second Language program. This is an increase of about 130 over previous years.

Among the innovative electives offered to the non-English speaking students are jazz chants, captioned rock videos and computer-assisted language learning. Nearly all of these people are preparing for the Test of English as a Foreign Language (TOEFL), a prerequisite for admissions at universities in the United States.

Approximately 900 high school students, who met selective guidelines for admission--SAT scores above 1200 and a B average--must enroll in two courses.