Following an established REL Northeast & Islands research protocol, we conducted a search for recent research on early admission to kindergarten. We focused on identifying resources that specifically addressed research on whether students who are admitted early have more challenges than their peers. The sources searched included ERIC and other federally funded databases and organizations, academic research databases, and general Internet search engines (For details, please see the methods section at the end of this memo.)

We have not evaluated the quality of references and the resources provided in this response and we offer them only for your reference. Because our search for references is based on the most commonly used resources of research, it is not comprehensive and other relevant references and resources may exist.

Research References

1. Baber, M. A., Ahmad, N. (2017). Role of Starting School Age in the Academic Performance at the Tertiary Level. Journal of Education and Educational Development, 4(2), 284-300.
   https://eric.ed.gov/?q=&id=EJ1161483
   From the abstract: “The purpose of this research was to find out whether starting school earlier than four years of age gave any academic benefit to the students in the long run. This research aimed to find out whether the students who started schooling earlier than four years of age are able to achieve better grades and are better at self-regulation at the tertiary level. For this purpose, a sample of 108 students from a private business school comprising both early and late school starters were made to fill in questionnaires reporting their school starting age, their CGPA and answering questions that showed their level of self-regulation. The findings of this study suggest that there is no difference in the academic performance of the two groups, both in terms of their CGPA and their self-regulation skills.”
2. DeCicca, P., Smith, J. (2011). "The long-run impacts of early childhood education: Evidence from a failed policy experiment," (NBER Working Paper No. 17085). Cambridge, MA: National Bureau of Economic Research.
   www.nber.org/papers/w17085
   From the abstract: “We investigate short and long-term effects of early childhood education using variation created by a unique policy experiment in British Columbia, Canada. Our findings imply starting Kindergarten one year late substantially reduces the probability of repeating the third grade, and meaningfully increases in tenth grade math and reading scores. Effects are highest for low income students and males. Estimates suggest that entering kindergarten early may have a detrimental effect on future outcomes.”
3. Dhuey, E., Figlio, D., Karbownik, K., Roth, J. (2018). School Starting Age and Cognitive Development. Working Paper 191. National Center for Analysis of Longitudinal Data in Education Research (CALDER).
   https://eric.ed.gov/?q=&id=ED591817
   From the abstract: “We present evidence of a positive relationship between school starting age and children's cognitive development from age 6 to 18 using a fuzzy regression discontinuity design and large-scale population-level birth and school data from the state of Florida. We estimate effects of being old for grade (being born in September versus August) that are remarkably stable -- always around 0.2 SD difference in test scores -- across a wide range of heterogeneous groups, based on maternal education, poverty at birth, race/ethnicity, birth weight, gestational age, and school quality. While the September-August difference in kindergarten readiness is dramatically different by subgroup, by the time students take their first exams, the heterogeneity in estimated effects on test scores effectively disappears. We do, however, find significant heterogeneity in other outcome measures such as disability status and middle and high school course selections. We also document substantial variation in compensatory behaviors targeted towards young for grade children. While the more affluent families tend to redshirt their children, young for grade children from less affluent families are more likely to be retained in grades prior to testing. School district practices regarding retention and redshirting are correlated with improved out- comes for the groups less likely to use those remediation approaches (i.e., retention in the case of more-affluent families and redshirting in the case of less-affluent families.) Finally, we find that very few school policies or practices mitigate the test score advantage of September born children.”
4. Furlong, M., Quirk, M. (2011). The Relative Effects of Chronological Age on Hispanic Students' School Readiness and Grade 2 Academic Achievement. Contemporary School Psychology, 15, 81-92.
   https://eric.ed.gov/?q=&id=EJ934708
   From the abstract: “This study examined the relations of age, preschool experience, and gender with children's school readiness levels at kindergarten entry. The sample included 5,512 children of predominantly Hispanic heritage and from families experiencing low socioeconomic circumstances. A series of between-subjects ANOVAs indicated that age ("Eta"[superscript 2] 0.019 to 0.043), preschool experience ("Eta"[superscript 2] 0.104 to 0.204), and gender ("Eta"[superscript 2] 0.015 to 0.022) were significantly related to children's school readiness as measured by the Kindergarten Student Entrance Profile (KSEP). Logistic regression examined the unique contribution of these variables to predict students' academic achievement at the end of Grade 2 with a subsample of 980 students. The strongest achievement predictor was school readiness--the odds of students rated in the top 25% on the KSEP having proficient or advanced scores on the English Language Arts portion of the California Standards Test at the end of Grade 2 were 4.51 greater than the odds of students rated in the bottom 75% on the KSEP having proficient or advanced scores. Similar results were found for students' achievement in mathematics. The key findings of this study showed that formal preschool experiences play an important role in preparing children of Hispanic descent and who live in households experiencing low income for kindergarten entry. However, children's readiness at entry into kindergarten was more strongly related to later academic achievement than age at kindergarten entry and preschool experience. (Contains 1 figure and 3 tables.)”
5. Hover, A.(2018). Making Informed Decisions about Academic Redshirting and Retention through School and Community Partnerships. International Journal of Whole Schooling, 14(2) 53-62.
   https://eric.ed.gov/?q=&id=EJ1190027
   From the abstract: “School administrators and teachers create a culture for high learning and achievement when they partner with parents to make decisions regarding the optimal age to begin formal schooling. The age that students begin school has decreased across the globe; however, the United States has various eligibility dates for school entry that require children to begin kindergarten at older ages. A large amount of research suggests that there is an achievement gap between students whose ages are close to the eligibility age for school entry when they begin kindergarten compared to students who begin kindergarten at an older age. Parents often attempt to reduce the potential that their young children will experience school failure by "redshirting" them for a year before enrolling them in kindergarten; however, many parents cannot afford to pay for another year of childcare so they enroll their children in kindergarten with the possibility of retaining them and repeating kindergarten. Some researchers assert that there are no positive long- term effects to redshirting children. Children grow and develop at various rates; therefore, parents and educators must collaborate to decide when a child will begin public school based on individual social, emotional, and academic needs.”
6. Yesil Dagli, U., Jones, I. (2012). The Effects of On-Time, Delayed and Early Kindergarten Enrollment on Children's Mathematics Achievement: Differences by Gender, Race, and Family Socio-Economic Status. Educational Sciences: Theory and Practice, 12 (4) 3061- 3074 Aut 2012.
   https://eric.ed.gov/?q=&id=EJ1003000
   From the abstract: “This study was an examination of the effect of delayed, early, and on-time kindergarten enrollment on children's kindergarten mathematics achievement. Central for this study was to explore if the relationship between the kindergarten enrollment status and mathematics achievement varies by children's gender, race, and family SES status. It used a nationally representative sample of ECLS-K data collected in the United States of America. On average, findings of this study suggested that children with delayed enrollment in kindergarten had stronger mathematics skills than children with on-time enrollment in kindergarten, who had stronger skills than children with early enrollment. However, this pattern of relationship appeared to be different for children from lower socioeconomic background and children from racial minority groups by their gender. (Contains 3 tables and 12 figures.)”

Methods

Keywords and Search Strings

The following keywords and search strings were used to search the reference databases and other sources:

Early admission to kindgergarten

Early entry to kindergarten

Kindergarten age four

School entrance age

Kindergarten entrance age

Age differences kindergarten

Kindergarten four years

Kindergarten age

Early kindergarten enrollment

Transitional kindergarten

Early kindergarten

Age effect kindegarten

Databases and Resources

We searched ERIC for relevant resources. ERIC is a free online library of over 1.6 million citations of education research sponsored by the Institute of Education Sciences. Additionally, we searched Google Scholar and PsychInfo.

Reference Search and Selection Criteria

When we were searching and reviewing resources, we considered the following criteria:

Date of the publication: References and resources published for last 15 years, from 2002 to present, were included in the search and review.

Search Priorities of Reference Sources: Search priority is given to study reports, briefs, and other documents that are published and/or reviewed by IES and other federal or federally funded organizations, academic databases, including WWC, ERIC, and NCEE.

Methodology: The following methodological priorities/considerations were given in the review and selection of the references: (a) study types – randomized control trials, quasi experiments, surveys, descriptive data analyses, literature reviews, policy briefs, etc., generally in this order; (b) target population, samples (representativeness of the target population, sample size, volunteered or randomly selected, etc.), study duration, etc.; (c) limitations, generalizability of the findings and conclusions, etc.