UPDATED: February 1, 2013, at 11:16 p.m.

Approximately 600 students spilled out of Fong Auditorium on Wednesday for Folklore and Mythology 90i: “Fairy Tales and Fantasy Literature”—nearly twice as many as had shopped the class last year. The overwhelming interest dwarfed Pre-Term Planning expectations, which projected that about 400 students would shop the course. And of those nearly 600, only 45 were accepted after a lottery that left hundreds of students without the chance to take their first-choice class.

As the number of interested students in some already oversubscribed classes continues to grow and Pre-Term Planning data at times fails to accurately predict student interest, professors face the dilemma of how best to accommodate students while still maintaining the quality of their classes.

“It always feels distressing,” Maria Tatar, instructor of Fairy Tales and Fantasy Literature, said of having to lottery her course.

“After the lottery, I always get a flood of emails asking to be put on the waitlist. I realize that in the grand scheme of things, it doesn’t really matter—there are hundreds of other great courses in the catalog—but it’s not a feel-good experience.”

Ryuichi Abe, who teaches Aesthetic and Interpretive Understanding 36: “Buddhism and Japanese Culture,” wrote in an email that he was able to plan for higher student interest thanks to a notification from the General Education office over winter break indicating potential increases in enrollment.

But even planning in advance was not enough. Abe recruited three teaching fellows to lead six sections and 108 students—a 71.4 percent increase from the year before—but 344 students entered his lottery this week.

English professor Helen Vendler’s Gen Ed course Aesthetic and Interpretive Understanding 20: “Poems, Poets, Poetry” expected a little over 90 students but saw more than 200 show up at the first lecture.

Pre-Term Planning data and actual student interest do not always align, as evidenced by this semester’s shopping week. But Administrative Director of the Program in General Education Stephanie H. Kenen wrote in an email that the Pre-Term Planning process, which was introduced in late 2010, is still evolving.

“We are still learning about how to interpret these numbers while allowing students the freedom to visit courses during shopping week,” Kenen wrote.

She added that Gen Ed courses are often lotteried due to a lack of resources. In other cases, such as when professors are introducing new courses to the curriculum, limiting enrollment can help the teaching staff adjust.

“Often a lottery is the best way to ensure that a course will run smoothly and provide the best learning environment for our students,” Kenen wrote.

The Gen Ed office has a general policy that lotteries be run randomly, she added, although there are certain exceptions. Abe, for example, was granted permission to give preference to students studying East Asian Studies. Similarly, Tatar grants priority to folklore and mythology concentrators and seniors who have been lotteried out of the course twice.

Vendler was able to hire enough teaching fellows to accommodate the unexpectedly high turnout for her Gen Ed course and said she is thankful to have avoided a lottery.

“I know how disappointing a lottery is,” Vendler said.

—Staff writer Madeline R. Conway can be reached at mconway@college.harvard.edu.