Sensing that her background in biology was lacking, Hanley enrolled in "Introduction to Immunology", a course taught by Gerald B. Pier, an assistant professor at the Medical School.

Pier's course is perennially one of the most popular courses offered. This year it ranked second with an enrollment of 146 students, just behind "Financial Accounting" with 206 students. The success of the course is due to the broad-based appeal of immunology in the medical sciences, Pier says.

"Most of my students probably aren't studying immunology," he says, "But they use it in their work. They may be researchers, health care workers, nurses, or even physicians who haven't had strong backgrounds in biology and suddenly find they need it."

Studying for Fun

Most students, however, say they take Extension courses simply for their own enjoyment.

"Our Extension program is unique in that we have the highest percentage of students in the country who come here just for personal enrichment, not for degrees," Shinagel boasts.

One such person is Cantabrigian Martina B. Lesser, 27, a social worker employed by the city to work in the Central Square area. She is taking "Behavioral Ecology" simply because the subject matter interests her.

"I also wanted to keep in the habit of studying," she adds, "Because someday I may try to get a masters in social work."

Students also provide a variety of reasons for choosing Harvard over other night and part-time schools in the area. Liora L. Gates, 28, of Jamaica Plain, is a scientist for Cambridge-based BioGen. She says she chose Harvard because it was conveniently located near the research firm.

While Page feels that the University's name ensures quality, Lesser gives different reasons for picking Harvard. "I live nearby, it was reasonably priced, and there was a good variety of classes to choose from," she says.

Willer says he chose this school because an undergraduate friend recommended it. He also claims that Harvard's prices are up to one-third less for similar courses offered at Boston College.

Part-time students generally seem pleased with the quality of their Harvard classes. In a survey taken at the end of last year, students were asked to rate their courses and professors on a scale from one to seven. The courses netted a 5.7 approval rating, and teachers earned a 5.8.

Professors, in turn, are quite happy with their students. In a similar survey, a majority of professors found Extension School students "more willing" or "more prepared" than their undergraduate counterparts.

"Extension students have stronger backgrounds in molecular biology and bio-chemistry than medical school students," Pier says. "They are clearly being educated with modern concepts."

Thomas C. Rounds, an assistant chemistry professor at Tufts, agrees. He finds the students in his course, "Physical Chemistry with Bio-Chemical Applications", are for the most part "more mature, and able to work on their own." This, he says, is a great advantage over teaching undergraduates.