Small Classes are Key to Universal Preschool Gains

Originally published by MinnPost on April 2nd, 2021.

By: Arthur J. Reynolds

The multitrillion dollar economic plans that President Biden rolls out this spring promise major infrastructure investments. One of them is universal preschool funding for all 3- and 4-year-olds. This is great news for families and young learners. To be successful and effective, however, the elements essential for sustaining learning gains must be present.

Addressing the key elements, described as essential for program effectiveness, small class sizes are the most underrated of all. They deserve to be front and center in any expansion initiative. The reason is that every great program starts with a sound structure. That means leadership, organization, and of course teachers who are well-trained and compensated. Small classes, which I define as no more than 17 children in either part- or full-day formats, have a long history of success as an essential element.

First, all the landmark early childhood programs demonstrating long-term gains into adulthood and high returns on investment had class sizes no higher than 17 or child/staff ratios of 17/2. This is described in the 2019 Cambridge University Press book Sustaining Early Childhood Learning Gains: Program, School, and Family Influences (Arthur Reynolds & Judy Temple, Editors).

Second, research syntheses over decades by the Washington State Institute of Public Policy shows that reducing class sizes is significantly associated with greater learning gains and that this advantage increases for the youngest students. This does not include professional learning opportunities that would surely enhance instruction.

A third source of evidence of the key importance of small classes is from a natural experiment in the Saint Paul Public Schools from 2012-2014. In the first year of the scale-up of the Child-Parent Center program directed by HCRC, preschool classes in all participating schools were 17. Large gains in school readiness were found. In the following year, the district increased class sizes back to the usual 20. Despite having the same teachers who had one more year of experience in a new program, learning gains dropped by 3 months compared to the first year. This take-away experiment shows the clear benefits of small classes in a contemporary, public school program. This advantage occurs regardless of family economic circumstances.

Near equal in importance, however, is that teachers prefer smaller classes and their satisfaction and enthusiasm for teaching is crucial for children’s success. Moreover, other essential elements such as child-centered, responsive instruction and learning time are more effective in the presence of small classes.

Minnesota and most states have a hodgepodge of programs, services, and funding that have no common structure of effectiveness, and do not recognize small classes as an essential element. Nor is universal access a priority. Even those with universal access or close to it do not implement small classes and many other key elements.

Now is the time to front-run the universal preschool movement by putting in the essential elements before a system and approach is established that does not follow the evidence. In a truly Great Society, being bold is not enough. We also have to be right.


Arthur J. Reynolds is Co-Director and Professor at the Human Capital Research Collaborative (HCRC) at the University of Minnesota. The center conducts research on cost-effective social programs spanning early childhood through high school.



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Instructional Continuity from PreK to Kindergarten Matters

By: Jasmine Ernst & Arthur J. Reynolds

PreK-to-3rd-grade (P-3) initiatives and programs are increasing in priority across the nation. The two major reasons for this are to (a) improve children’s learning during the key years of schooling and (b) ensure that PreK gains are sustained over time [5].

A critical mass of research, including our own, demonstrates that continuity in instruction from preschool to kindergarten benefits young children’s learning [5]. A combination of teacher-led lessons and child-initiated exploration in both PreK and K is associated with higher academic performance, and child-initiated exploration into kindergarten can provide an extra boost in academic performance beyond the benefits from PreK instruction [2: Ernst, J.R., & Reynolds, A.J. The added value of continuing child-initiated instruction from preschool to kindergarten: relations to academic achievement. (Poster)].

Instructional continuity refers to providing a consistent approach to classroom instruction from one year to the next. This alignment promotes learning, exploration, helps children know what to expect in the classroom, and eases transitions.

There are multiple aspects of instruction that can contribute to continuity, but here we will be focusing on two instructional approaches: teacher-directed and child-initiated instruction.

Teacher-directed instruction involves the teacher leading structured lessons. This usually involves the teacher leading a lesson for the whole class at one time.

Child-initiated instruction involves letting children explore by providing a variety of options and letting them choose where to spend their time. This is commonly seen during center-time or other kinds of free-choice time.

Many studies of the P-3 Child-Parent Centers have found that a combination of teacher-directed and child-initiated instruction in PreK is associated with higher academic performance sustained through 8th grade, higher income in adulthood, and greater educational achievement [1: Ernst, J.R., & Reynolds, A.J. (2020, July 21-23). Why preschool instructional approaches matter? Adult well-being outcomes in a low-income sample. [Poster], 34].

Recently, we found that continuing child-initiated instruction in kindergarten provided an extra boost in reading scores for children already exposed to teacher-directed and child-initiated instruction in PreK. This boost in reading scores associated with continuing child-initiated instruction into kindergarten was identified at the end of kindergarten, 3rd grade, and 8th grade [2].

Instructional continuity does not end in kindergarten! The positive benefits of participation in high-quality instruction for only one year can dissipate over time, and even if sustained, they are usually not large enough to substantially reduce achievement gaps. Research from the Child-Parent Centers indicates that high-quality education with an emphasis on P-3 continuity promotes sustained gains in achievement and positive adult well-being [5].

Ten Essential Elements of Early Childhood Program Effectiveness

By Dr. Arthur J. Reynolds

February 16, 2021

I have updated the key elements of effective early childhood programs to be consistent with the most recent knowledge on what works and what works better for young children and families. The original elements were articulated in collaboration with the Minnesota Department of Education in 2006.

Given the unprecedented health, economic, and social challenges facing the nation, high priority for action should go to solutions that demonstrate large, beneficial impacts. A key goal of President Biden’s policy agenda is universal preschool education for all 3- and 4-year-olds. Ensuring that scaled programs implement elements most likely to sustain gains will benefit children, families, and communities. 

The 10 elements are as follows:

1. Provide universal access for all children. The positive effects of early education on school readiness and performance have been found across all levels of socioeconomic status. 

2. Begin no later than age 4. Educational enrichment beginning early matters, but the evidence of benefits and long-term effects is strongest for programs serving 3- and 4-year-olds. 

3. Sufficient intensity of learning experiences. The instructional content and activities of programs should be of sufficient length and intensity to address learning needs adequately.

4. Multifaceted and engaging learning experiences across domains. A diverse set of instructional activities, curricula, and learning experiences help to promote active and engaged learning.

5. Highly trained professionals and on-going professional development. Children taught by BA-level teachers who are well-supported and compensated are more likely to experience high-quality programs. 

6. Accountability system marked by shared leadership, clear learning standards, and monitoring for improvement. A clear leadership vision is established that is shared and inclusive of all staff. 

7. Comprehensive family services.  Programs that provide a full range of child education and family services are more responsive to children's needs and will be more likely to impact child outcomes.

8. Small class sizes and low child-to-staff ratios.  Early childhood class sizes of less than 18 and child to staff ratios under 9 to 1 are associated with greater learning gains. 

9. Optimal duration and length. The number of years of preschool and the length of program services are positively associated with children's learning.

10. Coordination and alignment with K-3 to provide a continuous P-3 system of supports. The extent to which the preschool program is integrated with kindergarten and the elementary grades leads to smoother transitions to school and stronger gains. 


Two overarching principles should guide the implementation of the 10 essential elements.

A. A supportive and enriching organizational and social context for learning is foundational to optimal benefits and sustained gains. Elements of effectiveness in early childhood programs and broader learning systems achieve their most beneficial impacts within an organizational context that is well-supported by financial and human resources and promotes a collaborative and inclusive climate.

B. Gains are more likely to be initiated and sustained as the number of essential elements present in programs and classrooms increases. Studies in the Human Capital Research Collaborative have found that at least 60-70% of the key elements should be present to sustain gains.

Slideshow from 2/9/21 Lunchtime Talk:

File hcrc_brown_bag_feb_9_2020_essential_elements.pptx


From Bad to Worse: Distress in the Childcare Workforce

By Dr. Judy Temple

February 9th, 2021

The childcare workforce in the U.S., already burdened by low pay, has been severely impacted by the pandemic as shown by employment data by the U.S. Bureau of Labor Statistics. But even before the pandemic, there were significant concerns about the high cost of childcare and the low incomes earned by providers. A 2018 report from the National Academies of Sciences stated that the ECE workforce was in extreme distress. The report described the pre-pandemic system of funding early care and education as “neither sustainable or adequate to provide the quality of care and learning that children and families need – a shortfall that further perpetuates and drives inequality.”

We need to improve upon this unsustainable, inadequate system. The Biden administration has proposed a sizeable infusion of spending nationwide to help stabilize the childcare industry to preserve the availability of childcare slots and limit income and employment losses. Child development experts have identified key elements of high-quality early care and education that can ultimately help contribute to kindergarten readiness yet even before the pandemic working parents struggled to afford care even with federal or state subsidies. Employees in this sector earning the lowest wages are those without a college degree, who disproportionately tend to be women of color.

While it makes sense that the childcare industry is procyclical with employment rising and falling with the business cycle, allowing childcare providers to close for good may imperil our economic recovery. Working parents will find it even harder than before to find good affordable care and good quality early learning opportunities. Policy efforts are needed to improve supply and reduce employee turnover by providing higher wages. The National Academies report cited above is of central importance in this endeavor.

Before the pandemic, I wrote this piece for the School’s Gender Policy Report. My brief report ended with this recommendation, which may be of greater importance now: As we attend to the need to improve early childhood education and care, policymakers and advocates must also attend to the need for a well-paid, low-turnover, professional workforce of providers. When ECE providers can make a living doing highly valued work, they can make a difference for American kids.

Evidence Matters Blog Series


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