Group Size - A Key Indicator of Quality
By Ruth A. Wilson Ph. D.

  If you had to describe the quality of child care programs, what would you say? Most of us associate quality with a “certain something” that is special, usually expensive, and difficult to first find and then keep. In the child care field, researchers have tried to be more specific by setting aside the term “quality” and looking at the variables that appear to be program quality indicators. In doing so, they have identified two types of indicators: Structural and interactive. Structural indicators of quality are especially useful since they can be quantified and measured, allowing researchers to estimate the relative quality of particular programs. They can also be regulated through licensing or used to set standards in accreditation systems and often provide a foundation or serve as a necessary condition for the presence of less tangible, interactive indicators (Hayes, Palmer, & Zaslow, 1990; Colbert, 2002).


Measurable Characteristics

   Researchers have identified three measurable structural program characteristics that make up what they call an iron triangle of variables: Staff qualifications, child-to-staff ratios, and group size. Of those three, staff qualifications and child-to-staff ratios are relatively easy to understand and measure – Mary has a CDA and works in a state where the required ratio for four-year-olds is one staff member for each eight children. The third variable, group size, which has been called the most important of the three, especially for three- and four-year olds, identifies the maximum number of children that should be grouped together. In Mary’s state, the maximum number of four-year-olds in the group must be limited to 16. (Hayes et al. 1990; Colbert, 2002; NHSPS, 2002, Standard 1.002).


How Does Group Size Effect Quality?

   A decade after researchers identified group size as an iron triangle variable in Who Cares for America’s Children (Hayes et al. 1990), the authors of Eagar to Learn (Bowman, Donovan, & Burns, 2001), concluded that “if there is a single critical component to quality, it rests in the relationship between the child and the teacher/caregiver, and in the ability of the adult to be responsive to the child” (p. 322). Group size works to raise program quality, not simply because there is magic in having a particular number of children gathered together, but because when the number of children is small, each child gets more individual attention and interaction is more likely. Small groups do not automatically produce quality; quality lies in what can be achieved because the size of the group is small. Group size is, therefore, a key indicator of program quality.


What Is Group Size?

   Regulations and quality standards define group size in various ways. The following definition borrows from a number of sources, including the National Health and Safety Performance Standards in Caring for Our Children (NHSPS, 2002, Standard 1.002):


            A specific number of children, distinct from the larger population of children, 

            who are together regularly and interact with each other, and with one or more 

            specific staff members, in an assigned space. The size of the group and required 

            number of staff are usually determined by the staff: child ratio set out in 

            legislation or quality standards.


   An exploration of the highlighted elements in this definition helps explain why group size is such a key indicator of program quality.


Groups Include a Specific Number of Children 

   The term “group size” refers to a specific number of children in a particular group. In most cases, that number is closely related to the number of children identified in the child-to-staff ratio set out in licensing requirements and is usually a multiple of that ratio. 

   For example, if your program has to meet a ratio of 5:1 (one qualified staff member for every five children), your group size requirement is likely to be ten or 15. If it is ten, your program can have no more than ten children in one area and those ten children must be supervised by two qualified staff members. If it is 15, you can have no more than 15 children in an area and they must be accompanied by at least three qualified staff members. When your ratio is 1:5 but there is no requirement for group size, you could have 20, 25 or more children with four, five or more qualified staff members all together in one area. In such circumstances, it would be difficult for the children to experience the benefits that result when the number of children in the group is also limited.

   If your program is a play group or another type not licensed by your state, or if you want to implement group size voluntarily, you can look for guidance in limiting the number of children in each of the groups in your care by referring to your state licensing rule or look to the accreditation criteria of the National Association for Young Children (NAEYC, 1998) or the standard in Caring for Our Children (NHSPS, 2002) (see accompanying chart). 


A Group Is Distinct from the Larger Population

   When children are grouped, the children see their group as the unit to which they principally belong, even though other children are enrolled in the program. The authors of Caring for Our Children see a parallel between the “home room” in a school setting and the “group” in child care. As they see it, in child care, the group is “the psychological base with which the child identifies and from which the child gains continual guidance and support in various activities” (NHSPS, 2002, Standard 1.002).


Groups Are Together Regularly

   To benefit from limiting group size (and remain in compliance with licensing requirements), groups must be maintained on a regular basis for most program activities. On the other hand, it is not necessary – or, possibly, even desirable – for groups to remain together at all times. On certain occasions, such as meal and snack times or during special functions, children may mingle with others, as long as it is safe and appropriate for them to do so. For example, for their safety, infants should be separate from older children, both indoors and outdoors. Similarly, it is usually not appropriate for school-age children to mix with younger children. In larger centers, groups are likely to be maintained for more of the time than in centers where the total number of children is smaller. 


Children Interact With Each Other

   Small groups help children develop social skills by providing them with consistent opportunities to interact with a limited number of children. Based on their ages, children can be grouped in two ways. In single-age groups, all of the children are approximately the same age, usually within a range that is stated in licensing requirements. In mixed-age groups, the ages of the children may vary, in response to requirements and also the ages of the children enrolled at a particular time. 

   The decision to create mixed-age groups may reflect a philosophical belief in the advantage of including older and younger children together (Katz, 1995), or it may simply be based on the actual number and ages of the children in a program. In many cases, because of their vulnerability, infants and toddlers are not permitted in mixed-age groups or, if permitted, the child-to-staff ratio for infants and toddlers must be maintained (NHSPS, 2002, Standard 1.002).


Children Interact With Specific Staff Members

   When children belong to smaller groups, they have more opportunities to interact with staff and when specific staff members are consistently assigned to a group, children are able to form relationships with them. The resulting interactions are of benefit to the children and a major reason why group size is an important quality predictor. To ensure that that such relationships develop, children must be able to interact regularly with a limited number of caregivers. From an administrative point of view, it is also helpful to ensure that at least one staff member has an opportunity to get to know each child and family well and is able to serve as a contact when issues arise.


The Group Occupies an Assigned Space

   To get maximum benefit from organizing children in small groups, each group must occupy an assigned space. Ideally, each group should have its own room. When a room for each group is not possible, the existing space should be organized so that one group is not distracted by the activities of the others. You can define the limits of each group’s assigned space with firmly anchored room dividers or items such as counters or shelves that will not tip over. Dividers should be high enough to prevent the children from moving between groups or observing what is happening elsewhere. When such barriers are not available, space can be defined for particular groups using familiar objects, colors, special carpets, or other means to distinguish specific group areas within the room. When defining space for infants, you need to ensure that they are safe from environmental hazards and away from the activities of older children. 


Legislation or Quality Standards

   When legislation or quality standards require the grouping of children, they also determine the characteristics of many other program elements, such as the size and type of the space they are to occupy. Although research points to the benefits of organizing children in small groups, licensing laws in many states do not require specific group sizes. For example, in 2004, 17 states still did not regulate group size for three-year-olds or five-year olds (NCCIC, 2004). 

   It is clear, however, that organizing children in groups does not depend on complying with legislation or meeting specific standards of quality. Any director or teacher can decide to place limits on the number of children and staff members interactions. Group size can be an effective indicator of the quality of care – and a tool for raising program quality – in any setting where large numbers of children are together. 


Change Has a Ripple Effect

   What might happen if you change the size of the groups of children in your care? You might find that group size is connected to aspects of the program you did not expect. You may find that a problem that you thought possibly solved with additional staff training sorts itself out rather well when you alter the way you group the children. Limiting the number of children in groups can be a practical tool for solving problems and making your work experience more rewarding. Group size is connected to seven elements of an early care and education program.


1. Allocation and Use of Space

   When the children in your care are divided into groups, one of the first things to consider is where in your facility to locate the groups. If you are meeting licensing requirements, your first priority will be compliance with those requirements. Other priorities involve organizing your space so that each group has a distinctive space for children participation in activities with as little distraction as possible. When you have decided on the space, ensure that the children will be safe there by checking to see barriers are secure and pathways are not occupied by other children.  


2. Assignment of Staff

   When children are organized into groups based on a required child-to-staff ratio, the number of qualified staff for each group will be determined by that ratio. For example, if the ratio is 1:5 and the maximum group size is 10, the director or staff supervisor will have to assign at least two staff to that group. Assigning staff to groups, however, is only a first step. It is also important to decide how the staff will relate to each other and the children. You can decide to keep 10 children together at all times and assign equal responsibilities to each teacher, which means the teachers cooperate with each other in planning activities and carrying out other tasks. Alternatively, one teacher may be more qualified or experienced than the other and may be designated a “lead teacher” with ultimate responsibility for the group, while the other serves as an assistant. 

   Also, you may decide to create two sub-groups within the larger group, giving each teacher lead responsibility for each group. For example, it may be helpful to separate the youngest children from the oldest at certain times of the day. You can do that by creating two sub-groups, each with its own teacher. Children who attend kindergarten on a part-time basis may be more advanced than their age mates or the slightly younger children in their group who have no school experience. 

   Dividing the children into groups or sub-groups may also give staff some welcome independence. When two or more teachers are assigned to a group, they may have conflicting teaching styles, or one who is relatively inexperienced may benefit from an opportunity to manage a group alone, at least for part of the day. 


3. Staff Interactions with Children

   When children are organized in groups, staff have many more opportunities for regular interaction with individual children. Positive interactions between staff and children have many benefits, such as opportunities for staff to observe children’s learning and growth and for the creation of positive adult-child relationships (Colbert, 2004). The effect of those benefits is best summarized in the conclusion from Eager to Learn in the observation that the relationship between the teacher/caregiver and the child may be the “single critical component” of quality (Bowman et al., 2001). 


4. Staff Supervision of Children and Behavior Guidance

   Organizing children in groups makes it easier for staff to supervise the children. Each staff member has immediate responsibility for fewer children and more opportunities to become familiar with the behavior patterns, issues and concerns of individual children. When children are consistently in the same group, they have an opportunity to get to know their caregivers. They have opportunities to observe staff behavior and to model their own behavior according to what they see. 

    When groups are small, staff have a greater ability to take preventive measures before behavior management issues develop into full-blown tantrums or other problems. As they intervene with individual children, staff have opportunities to teach problem solving and re-direct behavior. When groups are large, staff must spend more time on custodial issues and have fewer opportunities to relate to individual children. It is more difficult to take preventive measures, children are more likely to be involved in conflict and miss opportunities to observe positive problem-solving behavior. 


5. Staff Working Conditions, Morale and Behavior

   When administrative decisions make affirmative relationships with individual children possible and support efforts to guide behavior in ways that reduce conflict, staff will respond in positive ways. Staff response is also likely to be positive when they are given clearly defined responsibilities and opportunities to work with others in a structured environment. When children are organized into groups and sub-groups, each staff member may have fewer children to supervise, but must be willing to accept the challenge of relating to individual children in more complex ways. Staff who accept that challenge are likely to appreciate the improved working conditions that often accompany the organization of children into groups. The increased morale generated is also likely to translate into positive relationships with both children and other staff members and may help stabilize staff turnover, which in itself will help improve the quality of care (Hayes et al., 1990; NHSPS, 2002, Standard 9.047). 


6. Program Decisions and Daily Schedule

   The grouping of children influences program decisions as well as the daily schedule. When children are grouped, staff have an opportunity to develop activities that are appropriate to the characteristics and abilities of the children in particular groups. On the one hand, they may decide to create groups of children of similar ages. Groups (or sub-groups) of older children will be able to participate in more complex activities than comparable groups of younger children. They are also likely to complete similar tasks within different timeframes. By grouping children according to their stage of development and abilities, staff can prevent behavior issues that arise when children are not sufficiently challenged or, conversely, are frustrated by tasks that are too difficult. On the other hand, staff may choose to include a variety of ages in a group to accommodate children who mature at different rates and to help children learn from each other, with the older children serving as models for younger ones. 

   The decision to group children brings with it consideration about when the children will be together and when they will be in their groups and/or sub-groups. Thought needs to be given to which grouping is most appropriate for a given activity and how to transition the children from one group to another. Transitions can be signaled by flicking the light switch on and off to indicate that one type of activity is over and another is about to begin. Children can be taught this signal to start cleaning up in anticipation of something new. Conversely, this transition can be “seamless” – children can leave a structured group activity one-by-one as they complete it, and move to play on their own or join an informal group. 

   When making decisions about programming or scheduling, it is important to know your staff and children and take into consideration the size of your program and facility. In some cases, it is appropriate for all children to eat together. In others, it is better if the groups eat separately. In still others, it is best if small sub-groups eat together. You may decide that sub-groups should eat together each day because of their maturity or because you wish to foster the development of relationships among the children.


7. The Children’s Experiences

   While the grouping of children has significant impact on the operation of a program and the staff, it is ultimately designed to influence the experiences of the children enrolled in the program. Research has shown that the size of the group influences both the development of individual children and the nature of the interactions that make learning possible (Colbert, 2004). The effects of group size have been observed in the various domains of individual development: Physical, cognitive, social and emotional. They can also transform the group from something more than a number of children into a genuine “learning group” with the power to foster and support the development of each child as an individual and a member of a social group of adults and children. 



Group size is connected to many aspects of early childhood programming. If you have to implement group size to meet a mandatory requirement, you will need to be prepared for a number of changes. You can get the greatest benefit from limiting group size if you know in advance where such changes might occur. On the other hand, if you decide to implement group size voluntarily, you are choosing a tool that can help you solve problems and meet many 

program goals. 


Judith Colbert, Ph.D., is a consultant who specializes in early care and education. She is the author of several articles on curriculum and a major study on the relationship between brain research and curriculum.



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