Is California’s New Universal Transitional Kindergarten Working?

When California makes a major public investment intended to improve opportunities and outcomes for young children, we should know whether it is achieving its goals—and what we can learn to make it work even better.

The case of universal transitional kindergarten (UTK) in California today provides an opportunity to ask whether a major investment is working.

As of last school year, all 4-year-old children were guaranteed a spot in a new grade called transitional kindergarten, or TK. Collectively, studies show that while high-quality early childhood education (a broad category encompassing educational programs for infants and toddlers, preschool or pre–K and transitional kindergarten) can have lifelong benefits, program design and implementation are key for achieving those goals.

Yet, now starting its second year of universal TK, California does little evaluation of the program, even though there is a compelling case for doing so. Worse, the lack of research and evaluation is part of a broader gap in California education policy. We do not consistently evaluate major investments.

By signing Assembly Bill 130 in 2021, Gov. Gavin Newsom took the final step in bringing universal transitional kindergarten to every school district in California. The expansion was a major investment. The Legislative Analyst’s Office reported in 2025 that the state’s investments to support UTK cost about $1.2 billion in one-time funding for facilities, planning and for increasing the number of highly qualified state preschool and TK teachers. In addition, in the 2025–26 budget for the program’s ongoing expenses, lawmakers included $3.3 billion for UTK students (under the Local Control Funding Formula and for the required 10:1 student-to-adult staffing ratio).

Policymakers in the years leading up to the expansion argued that more investment was needed because many children had insufficient access to early childhood education and were missing out on its potential benefits. High-quality research studies have found that the long-term benefits of preschool include better middle school outcomes (e.g., Tulsa universal preschool), higher high school graduation rates, more financial stability and fewer interactions with the justice system (e.g., Perry Preschool study, Child-Parent Center study in Chicago), and even better physical health (e.g., Carolina Abecedarian Project).

Looking more closely at the evidence around the outcomes of early childhood education, however, paints a more nuanced picture of the likely benefits. A randomized controlled trial that followed Head Start students into third grade found positive early impacts of Head Start, but that those effects had “faded out” by third grade. (Other research suggests the cause might be poor alignment of K–3 teaching and learning, which leads to calls for greater curriculum and teacher training coherence.) More recently, a study of a scaled-up, state-supported pre-K program in Tennessee found initial benefits of the program in kindergarten, but negative effects by sixth grade on several measures—state achievement test scores, disciplinary infractions, attendance and receipt of special education services. The authors suggest that an overfocus on behavior control (instead of play-based learning that is supported by research) and emphasis on early academic skills without aligning with curriculum in first, second and third grades may explain these effects.

Variation in outcomes across early childhood programs makes it especially important to study policies like UTK. Looking across the research, a RAND analysis of 115 evaluations of early childhood programs across the country found they range substantially in both approach and short- and longer-term outcomes. The analysis recommended paying attention to the quality of the program and conducting multifaceted evaluation of program implementation and outcomes. A Brookings Institution Task Force report on the evidence around pre–K concluded that “continued implementation of scaled-up pre–k programs is in order as long as the implementation is accompanied by rigorous evaluation of impact.”

This raises the question of how California is doing in evaluating TK, both to see if it is meeting policy goals and to learn how to improve program implementation. The broadest evaluation of California’s UTK has been conducted by the Learning Policy Institute, which notes that the potential of the investment will be fulfilled “only if implemented … with research-based elements of high-quality preschool.” Unfortunately, the data source the evaluation relied on does not provide the in-depth information needed to assess the quality of implementation. Anecdotal evidence shows challenges with the early rollout as well as the effects of TK on the broader early childhood workforce.

Unfortunately, UTK is not the only investment in education that doesn’t receive the examination necessary to improve implementation and determine if a program is meeting its goals. Even modest investments in the type of evaluations necessary to support improvement would go a long way. For example, the Expanded Learning Opportunities Program funds before- and after-school and summer programming for students in TK–6. It is the state’s second-largest “categorical” program (that is, dollars are restricted to a specific purpose) – education and services outside of school hours—funded at $4.7 billion for 2026–27. This program is also not evaluated.

A recent Policy Analysis for California Education (PACE) report named consistent evaluations as an essential function of a coherent education system. That is currently missing in California. How do we fix this? Lawmakers, when they pass bills, should require studies of the implementation and impact of major policy investments like universal transitional kindergarten. California needs to know whether UTK—and other major investments—achieve their stated goals.  

This commentary was originally published by EdSource on September 25, 2026.