Class and Classroom Scheduling

The Office of the University Registrar works with school and departmental staff in the following schools to create and schedule courses and classrooms each term:  Graduate School, Nicholas School of the Environment, Pratt School of Engineering, Sanford School of Public Policy, and Trinity College of Arts & Sciences. 

Departments use CourseLeaf Section Scheduler (CLSS, pronounced “class”) to submit scheduling requests to the Office of the University Registrar (OUR). The OUR then updates the data in DukeHub. CLSS tracks scheduling requests and checks for compliance with the Course Scheduling Policy.

CLSS URL (NetID and password required)

CLSS Access

To gain access to CLSS, submit the CLSS Access Request form.

CLSS Training

Training Guides

Helpful Tips and Important Reminders:
  • All additions, deletions, and revisions to your schedule must be submitted in CLSS.
  • Schedules must be validated prior to submission.
  • Classes are set up on the schedule according to how the courses are set up in the course catalog. This includes (but is not limited to): class permissions, prerequisites, REG codes, credits, and permanent crosslists.
  • CLSS pulls permanently crosslisted courses from the catalog, which are required to be scheduled. However, there is also the option to add one-time crosslists. IMPORTANT: Communicate with the department that you intend to crosslist courses with prior to adding the course to your schedule.
  • If you want to secure a room in the Link or ICC, please request the corresponding room characteristic and provide explanation for need in the Comments to Registrar section.

Have questions? Email

Undergraduate and Graduate Course Schedule, Courses Numbered 1-699
(Revised December 2022, Effective Fall 2023 Term)

Period 50-Minute Classes 75-Minute Classes 150-Minute Classes
1 8:45-9:35 8:30-9:45 8:30-11:00 or 8:45-11:15
2 10:20-11:10 10:05-11:20 10:05-12:35 or 10:20-12:50
3 12:00-12:50 11:45-1:00 11:45-2:15 or 12:00-2:30
4 1:40-2:30 1:25-2:40 1:25-3:55 or 1:40-4:10
5 3:20-4:10 3:05-4:20 3:05-5:35 or 3:20-5:50
6 4:55-5:45 4:40-5:55 4:40-7:10 or 4:55-7:25
7 6:30-7:20 6:15-7:30 6:15-8:45 or 6:30-9:00
8 7:30-8:20 7:30-8:45 7:30-10:00
Meeting Patterns
  • All classes, regardless of length, must align with the listed start and end times. Specifically, while classes may end before the listed end time, no class may end later than the noted end time.
  • 50-minute classes that meet three times per week will meet Monday, Wednesday, and Friday (MWF).
  • 75-minute classes that meet twice per week may meet Monday and Wednesday (MW), Wednesday and Friday (WF), Monday and Friday (MF), or Tuesday and Thursday (TTH).
  • 150-minute classes that meet once per week may be scheduled on any day of the week, in accordance with the constraints noted below
Distributional Constraints
  • Departments may schedule UP TO 50% of all of their classes below the 700 level during periods 2-4 ("prime time").
  • Departments may schedule UP TO 50% of their classes below the 700 level in the TTH meeting pattern.
  • AT LEAST 40% of all departmental course offerings below the 700 level must meet in some combination of two or three (or more) days per week or for two days per week in the MW, WF, or MF pattern.
    • Departments can offer any combination of three-day classes and two-day classes in the MW, WF or MF pattern in order to meet this constraint. The only stipulation is that departments must offer an equal number of MW and WF classes.
Special Circumstances
  • Departments offering six or fewer courses per semester at the 1-699 level do not have to meet any percentage constraints, but they are expected to provide a reasonable spread of courses over the day and week.
  • If departments offering ten or fewer courses at the 1-699 level in a given semester schedule at least one of those courses in the first period, they are permitted to schedule up to 65% (instead of up to 50%) of their classes in periods 2-4 ("prime time").
Further Clarifications
  • There are no percentage constraints on 700-level and above graduate classes.
  • For purposes of the percentage constraints, cross-listed courses count only for the department owning the course.
  • No TBAs for day and time may be submitted with the exception of independent studies and internships.
  • Half credit courses that stand alone, including house courses, performing arts courses, and physical activity courses, are not subject to the constraints, though departments are encouraged to provide a reasonable spread of these courses over the day and week.
  • The Office of the University Registrar reserves the right to require other schedule constraints not listed above depending on available classroom space.

Departments who wish to appeal any aspect of their course validation may do so via email to the Office of the University Registrar.

Revised December 2022

Effective Fall 2010 the Higher Education Opportunity Act of 2008 (HEOA) requires all institutions receiving federal financial aid to "publish," in time for registration, a list of all required and recommended books and other course materials for all classes offered at the institution. This includes all schools—undergraduate, graduate and professional. The items we must display are:

  • Book title, including edition
  • Book author
  • ISBN number
  • Retail price

This is an effort to make more transparent the cost of education, as indicated in the following statement from the HEOA:

PURPOSE AND INTENT—The purpose of this section is to ensure that students have access to affordable course materials by decreasing costs to students and enhancing transparency and disclosure with respect to the selection, purchase, sale, and use of course materials. It is the intent of this section to encourage all of the involved parties, including faculty, students, administrators, institutions of higher education, bookstores, distributors, and publishers, to work together to identify ways to decrease the cost of college textbooks and supplemental materials for students while supporting the academic freedom of faculty members to select high quality course materials for students.