Small classes ensure that universal preschool gains are sustained

Small classes ensure that universal preschool gains are sustained

Originally posted 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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By: Arthur J. Reynolds

Originally published by MinnPost