Deep Dives

The Issue

As a whole, small groups are commonly used in the classroom to engage students and bolster collaboration. Popular options include peer-to-peer dyads, teacher-led groups, or think-pair-share groups. In particular, teacher-led small groups are a means of providing a subset of students with targeted support, which is especially useful during literacy instruction. Plausibly, this creates a condition in which teachers can tailor their instruction to meet the needs of individual students, provide more responsive feedback, make meaningful adjustments to the difficulty of the content, and increase opportunities for students to respond. However, research across a series of interventions, meta-analyses, and systematic reviews has produced inconclusive results about optimal small group composition, when they are advantageous to alternative instructional formats, who they potentially advantage or disadvantage, and the conditions needed to produce the best outcomes. This leaves teachers with more questions than certainty on how to integrate small group instruction to best support students’ diverse instructional needs. Further, responding to the differences in students’ needs requires considerable planning time and intention; so if smaller groups are intended to create more opportunities for responsive instruction, why don’t they consistently produce better outcomes? What has to change?

The Research

As noted earlier, small groups allow teachers to adapt instruction so that students have more targeted opportunities to receive explicit instruction and practice key skills (Foorman & Torgesen, 2001; Siegal et al., 2024).

However, simply placing students into smaller groups does not guarantee that those instructional adaptations will occur (Deunk et al., 2018).

Instead, consideration must be given to many ways in which groups can be formed. For example, the students in your class scoring above benchmark on grade-level phonics measures could use a small group to build their comprehension skills. This would be a homogeneous (or students with similar performance) within-class group. Conversely, if students in your class and the other grade-level class have students who are below benchmark on oral reading fluency, then they may benefit from a small group addressing foundational skills (as seen with the walk-to-read model). This would be a homogeneous between-class group. Though more research is needed, the available evidence does not seem to suggest that either composition is superior (Matthew et al., 2013). Homogeneous small groups are commonly used at the elementary level (Graham et al., 2020); however, alternative options are available. For instance, heterogenous groups (i.e., with students of varying levels) may also be used, though much like with the homogeneous composition comparisons, there may not be superiority to this composition. Kieffer and colleagues found that on average, reading achievement didn’t differ significantly for English learners (ELs) randomly assigned to a heterogenous group with non-ELs, versus a homogeneous group exclusively composed of ELs (2025). However, there is an important nuance to these findings. How the grouping arrangement benefited certain students depended, in part, on their English proficiency. Students in the heterogeneous group benefited when they had a relatively higher English proficiency and could learn from more advanced students, whereas students in the homogeneous group benefited if they had lower English proficiency so they could better target foundational language skills.

Importantly, these results highlight that one grouping system may not be universally superior to the others. Instead, a group's effectiveness is a byproduct of how well it can accommodate the various needs of the learners within the group.

Another key consideration for teacher-led small groups is when to use them. For K-3 students, teacher-led small groups are commonly cited as being an effective instructional approach for targeting code-based skills such as phonemic awareness and phonics (Connor et al., 2011b; Foorman & Torgesen, 2001; National Reading Panel, 2000). Importantly, the advantage of small-group instruction relative to whole-group instruction may differ by skill as phonemic awareness instruction appears to be particularly beneficial in small-group delivery, whereas phonics instruction can be effective in both small- and whole-group formats. Given that emphasis is typically placed on code-based skills during this period, the utility of small groups may be to reinforce and facilitate these foundational literacy skills. However, as children progress to grades 3-5, more emphasis is placed on meaning-based skills such as comprehension. Though teacher-led small groups may still have positive effects on students (Connor et al., 2011a), alternative small group formats such as cooperative learning (Stevens, 2003) or reciprocal teaching (Palinscar & Brown, 1984) that offer students opportunities to make comments, give explanations, and provide peer feedback, may be well suited to support the development of meaning-based skills (Murphy et al., 2009). Teachers may opt to lead small groups to provide support for students who continue to struggle with code-based skills, but it should be relevant to their instructional needs. For adolescent students, there is surprisingly little to no research studying teacher-led small groups as a part of universal instruction. Instead, most of the available literature for older students focuses on more intensive interventions that can be used to support the wide range of their instructional needs (Burns et al., 2011; Little et al., 2014).

To add further complications, school administrators are often tasked with creating master schedules, thus creating more questions about optimal group size, frequency, and duration. This leaves teachers to not only make decisions about when to use small groups, but also how large those groups should be, how often they should meet, and how long each session should last. Transparently, much of the available guidance seems to be based on standards taken from response to intervention (RTI) guidelines (Gersten et al., 2009), but unfortunately, a universal standard does not exist. Some guidance suggests that groups of struggling readers should consist of 1-4 students, whereas students reading on grade level can contain 5-8 students (Florida Center for Reading Research [FCRR], n.d.). Turning to findings from intervention studies that use small groups for students struggling with reading, the recommendations are mixed based on students’ age. Studies of preschool and adolescent students suggest that the number of students in a group doesn’t significantly influence reading outcomes (Neuman & Kaeffer, 2013; Vaughn et al., 2010), whereas Vaughn and colleagues suggest that for elementary students, groups of 1-3 students have better outcomes than groups with more students (2003). This range of recommendations provides teachers with some flexibility to adjust group size based on the needs and grades of the students within the groups.

Similarly, guidance on how often and how long small groups should meet during universal instruction is limited to practitioner recommendations that are likely based on RTI guidelines, rather than experimental studies. For example, Tier 2 and 3 guidelines recommend meeting for 20-40 minutes approximately 3-5 times per week (Gersten et al., 2009). Following practitioner recommendations, teachers should be meeting with at least some of their groups daily during the allotted literacy block for 5-30 minutes (IRIS Center, 2006; FCRR, n.d.). In the absence of a one-size-fits-all guide, it may be helpful to consider what Connor and colleagues refer to as child characteristics by instruction, or CXI, interactions (2011a). In sum, this interaction posits that students' responsiveness to instruction depends on their individual language and literacy skills. As such, teachers may adapt how often and how long they meet with students during small groups in order to accommodate the unique needs of students. For example, a student who needs support with code-based skills and meaning-based skills may benefit from participating in two small groups to address their needs. Other students may benefit from meeting three times a week for longer periods, while some students may benefit from meeting for shorter periods every day. This allows for customization tailored to students' needs instead of strictly adhering to predetermined guidelines (Kosanovich et al., 2007).

Lastly, guidance suggests that groups should be continually reassigned to adjust to students' evolving needs (Siegal et al., 2024). By doing so, teachers avoid having students’ group assignments serve as a static label, as different benchmarks may reveal varying levels of strengths or areas for improvement. One common approach is to monitor and adjust by using progress monitoring data and curriculum-based measures. Connor and colleagues found that the teachers who spent more time analyzing their student’s progress monitoring data had students with greater reading gains (2011). However, data-based grouping decisions should also exist in conjunction with knowledge about how well students work with one another and whether opportunities exist for students of different strengths to support one another (Wilkinson & Fung, 2002). Though regrouping is a key consideration for small groups, research on how often to regroup is still underway.

In Sum

Small groups are a valuable tool that allow teachers to provide targeted instructional support for students' diverse literacy needs. There are several composition options, including homogenous and heterogeneous groups that can take place both within and across different classrooms. However, despite small groups being a valuable tool, it is important to confront that they are not always the most appropriate tool. Further, it is important to reiterate that it is not the small group itself that is valuable, but instead how instruction is modified within the small group that makes the difference. Research evidence is strongest for K-3 students when targeting foundational literacy skills, whereas research for older adolescent students is lacking. Recommendations for decisions such as group size, how frequently groups should meet, and duration are largely based on both intervention research and practitioner guidance, leaving teachers the necessary space to make adaptations suitable for their students.

Questions we just don’t have the answers to:

1. What are the long term effects of heterogeneous grouping vs homogenous grouping for students with different literacy needs?
2. Are there negative effects to regrouping students too often?
   1. What is the best regrouping sequence?
3. Are modifications to intensity, duration, or group size equally important for seeing gains in literacy for students, or do some modifications matter more than others?
4. Should small group instruction be applied differently at the beginning or end of a curricular unit or consistently throughout?
5. What does small group instruction look like for older students?
   1. Do suggestions for group size change as students get older?
6. How does the amount of time spent outside of a small group when completing independent/unsupervised work, impact reading achievement?
   1. Are some unsupervised tasks more effective for facilitating independent learning than others?

Nitty-gritty of some of the research:

Connor et al., (2011b)

Participants

• 369, 1st grade students across 7 different schools in North FL.

Study Design

• This study tested the effects of the Individualizing Student Instruction (ISI) intervention using the Assessment to Instruction (A2i) software, which provides recommendations for flexible grouping based on a student's code-based and meaning-based skills. 222 students were assigned to the treatment condition where teachers received professional development and used the A2i software whereas 174 students were assigned to the control condition in which teachers received written assessment reports in the fall, winter and spring of their students' progress to make instructional decisions without using the software. A subset of children were randomly selected for classroom observations to assess differences in instructional content, grouping arrangements, the length of time spent in groups, and whether the groups were led by teachers or if the students worked independently.

Findings

• Students in the treatment condition had significantly better gains in their word-reading ability, which was estimated as two months' worth of reading growth. Teachers in the treatment condition were also more likely to tailor their instruction to the students’ needs. Adherence to the recommendations was crucial because the more aligned the student’s instructional time was with the recommendations, the better they performed. However, if students simply received more time in code-based instruction, beyond what was recommended, there was a negative effect on reading outcomes.

Notes/Limitations

• The finding that excessive time spent receiving code-based instruction does not suggest that code-based instruction is wrong. Instead, the authors suggest that this provides evidence for their argument that instruction should be tied to the needs of the learner, instead of a one-size-fits-all approach. It is also important to highlight that the authors did take careful attention to match the control and treatment groups on factors such as the school's SES, or the number of students receiving ESE services. Lastly, factors such as transition time or disruptions were excluded when calculating the length of instruction, so these factors may have influenced the outcomes.

Vaughn et al., 2010

Participants

• 546, 7th & 8th grade students across 6 middle schools in the Southwest region of the U.S. Students were identified as struggling readers and the majority of the sample lived in an impoverished area.

Study Design

• Students were randomized into 1 of 3 groups to test the effects of their reading intervention compared to the typical school instruction and the effects of group size on the effectiveness of the intervention. The intervention was delivered daily for about 50 minutes during the school year, and targeted skills such as multisyllabic word reading, fluency, vocabulary, and reading comprehension in 3 phases. There were two treatment conditions (i.e., research small-group treatment or research large-group treatment) and a comparison group (i.e., school treatment). There were 3-5 students in the small group condition, 10-15 students in the large group condition, and 10-20 students in the comparison condition.

Findings

• Overall, students participating in the intervention outperformed students in the control condition; however, the smaller group size generally did not provide a statistically significant benefit compared to the larger group size. For word-reading fluency, several measures favored the small treatment group as compared to the large group and the comparison group, but the effects were small. The authors interpreted the findings by suggesting that older students with reading difficulties may need more than 50 minutes of daily reading instruction to lessen the gap in their literacy knowledge and that specific attention should be given to their extensive needs.

Notes/Limitations

• The main goal of this study was to test the effect of the group size while keeping the instructional content and length the same. The lack of meaningful effects favoring smaller groups may not be reflective of the fact that group size doesn’t matter, but instead that instruction may need to be modified within a group to better meet the needs of the students, especially when reading difficulties have been long-standing. Also, it is important to note that a large portion of students dropped out at some point during the study and some of the students received additional reading instruction outside of the intervention, so these factors have the potential to influence the findings. Lastly, since the intervention targeted multiple components of reading, it is difficult to determine whether the group’s size was more or less effective for a specific component (e.g., decoding multisyllabic words vs. discussing vocabulary).

Additional Resources:

Aligning Practice with Research: Using Small Groups to Differentiate Instruction

Differentiated Reading Instruction: Small Group Alternative Lesson Structures for All Students. Guidance Document for Florida "Reading First" Schools

Florida Center for Reading Research | Differentiated instruction