Harvard's Core Curriculum is bursting its seams, serving 6000 more students with 40 percent fewer courses than its six-year-old plan calls for, professors and administrators said this week.

Students trying to fulfill their distribution requirements amid a complex system of lotteries and limited offerings wind up in a few large courses, they said. This semester, eight of the 10 largest courses are in the Core.

The program must persuade more senior faculty members to teach the courses, Core Curriculum Director Susan W. Lewis said last week.

"When the Core was created, nobody thought it would be as big as this," said Lewis. The new courses were originally expected to attract about 10,000 students a year, she said. But today, upwards of 16,000 enroll in Core courses each year.

In addition, Associate Dean for Undergraduate Education David R. Pilbeam said the Core Curriculum now offers about 70 courses each year although the target number is 120.

"It's a struggle," Pierce Professor of Psychology Richard J. Herrnstein said of the recruiting effort among senior faculty members. "The older the Core gets, the more routine it becomes. I think it will get harder and harder," said Herrnstein, who chairs the Core's Social Analysis subcommittee.

"We are in a constant state of recruitment forcourses," said Pilbeam, adding that a "substantialchunk" of the senior faculty ought to assume theCore's heavy teaching demands.

Pilbeam said the chief cause of the crunch isthe fact that Harvard has a small faculty comparedto other major research and teaching institutions.

Dean of the Faculty A. Michael Spence, chairmanof the standing committee on the Core, said scarceresources and time make the recruiting job evenmore difficult. "The Core lands particularlyheavily in a number of areas and departments, andthis adds to the sense of having more commitmentsthan there are hours in the day," he said.

Spence said administrators should be"energetically encouraging" faculty to teach inthe Core and making sure that departments haveenough staff to meet both their own needs andthose of the centralized curriculum.

The recruitment process is a long and elaborateone, usually taking two years between proposal ofa professor to teach a Core course and the time itis first taught, administrators said.

"First there is wooing and then backing andforthing," Pilbeam said of the long process todesign Core courses. Each professor goes through arigorous series of proposals and meetings withmembers of the Core's subcommittees, he said. Andeach faculty member who gains approval for acourse must agree to teach it for three years,Lewis said.

Yet the two-year gap between idea and coursehardly seems to address the Core's pressing needfor an expanded slate of offerings.

The process can speed up for some professors.Lamont University Professor Amartya Sen onlyjoined the faculty last year, but he is alreadyteaching Moral Reasoning 36, "Facts and Ethics,"this semester. He said administrators urged him toteach in the Core when he first arrived atHarvard.

Administrators said haste in preparing thecourses was not the way to bolster the numbers offaculty teaching in the Core. But short of hiringmany more professors and lobbying those alreadyhere, they have found no answer to the dilemma,they said.

And the students who continue to flock to Corecourses will just have to hope they win thelotteries