With the first Monday of classes coinciding with Yom Kippur, the registrar has switched Friday and Monday classes to accommodate the Jewish holiday.
Classes will be on a normal schedule today, but tomorrow all students will head to the classes they would normally attend on Monday.
The swap completes Monday when the usual Friday courses will be held. After this one-time switch, normal class schedules resume on Tuesday.
The unusual calendar change allows Jewish students and faculty observing Yom Kippur, one of the holiest days of the Jewish year, to attend their first classes of the fall term.
Yom Kippur, meaning Day of Atonement, is a day where Jews throughout the world repent for their sins during the past year.
Because of the switch, and because most classes normally meeting Fridays would also normally meet Mondays, faculty and students observing the holiday will not have to miss the first meeting of the semester of any course.
"There are rational reasons behind such policies — basically it is allowing students to get to class," University Registrar Joseph Greenberg said.
The anticipated absence of the Jewish students, faculty and administrators on Monday seemed more disruptive than the class switch, he said.
The Faculty Committee on Classrooms and Schedule, a 13-member group including a rotating panel of seven faculty members, decided to bring the idea of the calendar switch to a vote at a faculty meeting earlier this year. The decision was announced in early August.
Though Greenberg said the group does not normally make adjustments to the calendar of this kind, the faculty members felt it was necessary.
To that end, the registrar has been working to get the word out and ensure a smooth transition. Details about the change have been posted on the University website, and several reminder e-mails have been sent to students during the past few weeks.
Because the Jewish calendar is lunar, the dates of holidays change each year. Next year Yom Kippur falls on Oct. 6, for example.

In the past, the committee has decided not to adjust the University calendar when Jewish holidays fell on weekdays because the change would probably cause too much confusion.
Future changes will depend on the specific situation.
At the Center for Jewish Life, the reaction to the calendar change is positive.
"I think that for all Jewish students and faculty for whom Yom Kippur is a central day, the schedule change is a most appreciated act of consideration," Rabbi James Diamond said.