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Schedules and Grouping

How can we structure student groups to maximize safety?

(This page is no longer updated and is kept here for historical purposes only. Please return to the main Health & Safety Guidebook page for the most up-to-date content and guidance). 


Because the virus that causes COVID-19 is more easily transmitted when someone infected is in close proximity to others, physical distancing and student grouping will be key factors in mitigating risk. Creating small stable groups of students and staff who stay together and avoid contact with other groups, sometimes called cohorting, is a necessary and powerful tool to prevent the spread of the virus that causes COVID-19 while also providing opportunities for in-person interaction in a safe context.


Implementing stable groups of students and staff reduces the numbers of exposed individuals if COVID-19 is introduced into the group; decreases opportunities for exposure to or transmission of the virus; facilitates more efficient contact tracing in the event of a positive case; and allows for targeted testing and quarantine of a small group instead of potential schoolwide closures in the event of a positive case or cluster of cases.



Grouping students into stable groups and sticking to Six Key Considerations can help increase safety. 

What Are Stable Groups? 

A stable group is a group with fixed membership that stays together without mixing with any other groups for any activities (e.g., lunch, recess). 


Stable Groups vs. Cohorts

Guidance from other agencies, including the federal Centers for Disease Control and Prevention (CDC), sometimes refers to stable groups as “cohorts” or “pods.” In California State guidance, “cohorts” has a specific meaning, which is a group of up to 16 individuals (students and staff) in a supervised environment in which supervising adults and children stay together for all activities (e.g., meals, recreation, etc.), and avoid contact with people outside of their group in the setting.


What Is the Purpose of Cohorts and Stable Groups? 

The goal is to reduce the number of people any individual is exposed to and to reduce the number of people in any given space. Utilizing stable groups minimizes the number of people exposed if a COVID-19 case is identified in a child attendee, provider, other instructional support provider, or staff member of a particular group. Stable groups provide a key mitigation layer in schools that should be used in addition to (not instead of) other safety measures like wearing face coverings. 


Examples of What Stable Groups Could Look Like

Below are some examples to illustrate what the implementation of stable groups could look like in LEAs. Each LEA should consider how to best implement the existing guidelines to serve their respective communities. 


How can an elementary school create stable groups?

  • Students can be grouped into stable groups that stay together all day with their core teachers, aides, and student teachers. If there are counselors or teachers of electives, they would ideally be assigned to only one group or conduct their classes or counseling virtually. 
  • Students should eat lunch and go to recess with their group at times that are staggered and separated from other groups.
  • There are different approaches to organizing stable groups. Students can be divided into smaller groups that attend school in person on a rotating schedule. Here are a few examples:
    • A group of students comes to school for in-person instruction on Monday and Tuesday. Another attends on Thursday and Friday. On the alternating days, they learn remotely.
    • Some LEAs or schools have had students attend school in-person during alternating weeks.
    • Other LEAs or schools have one group of students attend school in person in the morning and another group attend school in person in the afternoon.

These approaches create even smaller groups that stay together and do not mix with one another. Electives or counseling can be conducted virtually to limit the number of staff in direct contact with any given stable group.


How can a middle or high school create stable groups?

    • Students can be placed into groups that remain together all day during in-person instruction. Middle or high school groups are often larger than elementary school groups.
    • The CDC guidance notes that schools may keep a single group together in one classroom and have educators rotate between groups, or have smaller groups move together in staggered passing schedules to other rooms they need to use (e.g., science labs) without allowing students or staff to mix with others from distinctive groups.
    • Teachers and support staff from different content areas can work in teams that share students, preferably in a dedicated space, separate from others. For example: math, science, English, and history teachers might work as a team with a set group of students they share.
    • Combining grouping with block schedules that reduce the number of courses students attend in any one day, the number of educators and students who interact can be minimized further.
    • It is also possible to keep students in one stable group that stays together with one or two instructors who teach them directly part of the day and support their instruction from others who teach them virtually during other parts of the day.
    • Electives can be offered virtually or organized so that no group of students takes more than one elective in a term and the elective teachers do not work with more than one or two groups.
    • Stable groups could switch schedules or even membership after a break at the quarter, trimester, or semester in ways that support students being able to take additional classes without substantial group mixing.
    • The school year can be divided into even smaller time units—4 to 8 weeks, for example—in which students study one or two subjects intensively, completing all of the work they might normally have completed in a semester or a year. They stay in stable groups with only 1 or 2 teachers during this time. At the end of the unit, they switch schedules and groups to take 1 or 2 other courses, and so on throughout the year.
    • Additional examples of approaches to creating stable groups of students that limit the risk of transmission across large groups of students are available here



Exposure to people outside the stable groups or cohorts will exponentially increase exposure to the virus for all children and staff. Small stable groups and cohorts are only effective if the people within them are vigilant about not mixing with other people. (For more information, see the CCEE one-pager on stable cohorts.) Prevent interactions between cohorts, including interactions between staff assigned to different cohorts.


 Cohort Mixing Considerations:


  • Separate Spaces: Each cohort should use a separate room or space. 
  • Limit the Crossing-over of Staff: Ideally, supervising adults should be assigned to one cohort and work solely with that cohort. Avoid changing staff assignments to the extent practicable. Consider ways to keep teachers and paraprofessionals with one group of students for the whole day. It is important to minimize the number of cohorts other staff members (e.g., administrators, counselors, nurses, or specialist teachers) come into contact with, as they can transmit the virus from one cohort to another, thus greatly increasing the number of contacts for any given case.
  • Substitutes: Substitute providers who are covering for short‐term staff absences should only work with one cohort of children per day.
  • Moving Children Between Cohorts: Avoid moving children from one cohort to another, unless needed for a child’s overall safety and wellness.
  • Special Activities: Keep cohorts separate from one another including for special activities such as art and exercise. Stagger playground time and other activities so that no two cohorts are in the same place at the same time. 
  • Think Beyond the Classroom When Creating Cohorts: Assign children who live together or carpool together to the same cohort, if possible. If offering after (or before) school services, consider extending cohorts to include these programs to minimize inter-cohort exposure.
  • External/Additional Pods: External or additional pods created by parents, camps, child care arrangements, or the school that are outside of the core classroom cohort will create exponential risk to all children in all cohorts. If each child is part of one additional group beyond the classroom cohort, it introduces risk and exposes all people in any given pod. Make sure families understand the impact of pods and camp groups beyond the school day.

To address some of the child care challenges in their communities, some LEAs have created emergency child care centers on their campuses. The San Diego County Office of Education team has created guiding documents for districts creating emergency childcare centers to use.

  • Decide Whether or Not to Move Forward: 
    • The Emergency Child Care Toolkit will assist districts in exploring the various required components related to opening an emergency child care site. 
    • The SDCOE Child Care Process Map is a visual that demonstrates SDCOE’s action plan to support schools with emergency child care. 
  • Stay Informed: Learn more by reviewing these frequently updated FAQs.


Picking a Scheduling Model 

To ensure students are safe and learning, the use of space and time will be ever more critical. Schedule guidelines allow teachers to plan learning experiences with prioritized goals in mind; set clear expectations and communicate them to students and families; and, most importantly, build continuity, routine, and connection for students in a time of uncertainty. Picking a scheduling model that works for your school will be key to a successful year. 


Visit the Flexible Schedules section of CCEE’s Field Guide for Accelerating Learning, Equity and Well-Being for up-to-date information and suggestions on: 


For more information about how this tool was created and answers to other questions, see the FAQ section.  

The Health & Safety Guidebook for California LEAs
The Health & Safety Guidebook for California LEAs was developed in collaboration with the
California State Board of Education, the California Department of Public Health, and other technical assistance partners.