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Blog Post · November 21, 2023

Video: Assessing Transitional Kindergarten’s Impact on Elementary School Trajectories

photo - Preschool Age Children Interact with Teacher

California’s Transitional Kindergarten (TK) program provides an extra year of schooling within the K–12 system. Launched a decade ago with limited eligibility, TK will soon be open to all four-year-olds. Taking stock of the program’s impact so far—especially among multilingual and special education students—can help TK expansion succeed. In a recent presentation, PPIC researchers Julien Lafortune and Laura Hill discussed a new report that examines TK’s impact relative to other high-quality programs.

Evaluations of initial TK cohorts have found improved kindergarten readiness, and national research on early childhood education finds generally positive short- and long-term impacts. Little is known, however, about the longer-term impact of California’s TK program.

To learn more, Lafortune and Hill followed student trajectories from TK through grade 5 in five large, urban districts. They were particularly interested in TK’s impact on English Learner (EL) identification and reclassification as well as the identification of special education needs; students with these needs could benefit from additional services early on. To assess outcomes, they looked at standardized test scores; social-emotional learning (SEL) scores; and differences across demographic groups.

One key finding is that English Learner identification is more common in TK than in kindergarten. Hill noted that it’s important to ask if this is a result of over-identification, and to be concerned about stigmatizing young students who are developing language skills by classifying them as ELs. However, she added, “another important question is whether over-identification is better than possibly missing a chance to identify students and provide services.” She pointed to evidence that TK students identified as ELs were reclassified as English proficient fairly quickly as an encouraging sign.

Hill and Lafortune also found that TK’s impact on test scores was small and not statistically significant. What might this mean? “The key thing to remember,” said Lafortune, “is that our study is looking at TK impact relative to other early childhood education options.” More than half of California’s four-year-olds are enrolled in some type of preschool—such as Head Start or private preschool—many of which are high quality.

He also noted that TK’s impact is likely to change as the program evolves and expands. “In the early TK years, there were larger class sizes, and not as many programs were full-day. There were many issues still being worked out—including credentials and staffing. So it’s reasonable to expect that—certainly as it evolves during expansion—we might see some different impacts, not just on test scores but also on identification of special needs and social-emotional learning.”

Suggestive evidence of TK’s positive effect on social-emotional learning applies only to “English-only” students, raising concern about the absence of a positive impact on multilingual students. Hill noted that it would help to have more information about the EL programs and services TK students are getting. “We did see some suggestive evidence that dual-language learners who were in schools with high percentages of dual-language learners did have slightly more positive SEL outcomes,” she said. “That’s something to keep an eye on going forward.”


early childhood education English learners Immigrants in California K–12 Education social emotional learning special education test scores transitional kindergarten