Being a year older at kindergarten entry leads to higher initial achievement¶

Claim · All claims
Evidence · 1 study · causal r? · q3
Currency · newest study 2020 · checked against its sources 2026-10-16 (automated, 1 of 1 entry) · not reviewed by a person

Subclaims¶

q3 i? Older kindergarten entrants show higher initial achievement than younger entrants, per regression discontinuity estimates. → Angela Johnson 2020

Evidence¶

Angela Johnson 2020¶

Angela Johnson, Megan Kuhfeld. (2020). Impacts of school entry age on academic growth through 2nd Grade: A multi-state regression discontinuity analysis. NWEA Research working paper. https://www.nwea.org/research/publication/impacts-of-school-entry-age-on-academic-growth-through-2nd-grade-a-multi-state-regression-discontinuity-analysis/ doi:10.1080/19345747.2021.1894519

q3 · i? · causal · r?

Multi-state regression discontinuity analysis of assessment data from three states, reported in the paper's abstract. The authors state that "Being a year older leads to higher initial achievement"; no effect size is printed in the available text.

"Being a year older leads to higher initial achievement and higher kindergarten growth rates but lower growth rates during 1st and 2nd grades."

Studies bearing on this claim¶

Does being older at school entry, or older than one's classmates, give a lasting achievement advantage? This table gathers the studies behind this claim and the 7 narrower claims that bear on it: 5 distinct studies (3 associational, 1 causal, 1 review), q2–q3, 0 of 5 with an effect size coded. One row per study, codes as each entry records them; no effect is averaged and no verdict is drawn. Built by scripts/synthesize_claim.py from eval/synthesis/; a row that looks wrong is fixed on the claim it comes from.

Discussion¶

Learner Variables¶

• Age and Developmental Stage — predictor: learners who differ on it differ in outcomes

Related Claims¶

• Older entrants show higher kindergarten growth rates but lower growth rates in 1st and 2nd grades — related
• The school-entry-age findings were produced with a multi-state regression discontinuity analysis covering academic growth through second grade — related
• Kindergarten entry-age effects do not differ by gender or race — related
• At the end of first grade, children whose kindergarten entry was delayed demonstrated slightly higher reading knowledge and skills than those who started on time — related
• At the end of first grade, children whose kindergarten entry was delayed were behind their classmates who began kindergarten on time in math — related
• Prior evidence on school entry age lacked causal estimates of growth through early grades — related
• The entrance-age achievement association appears in the first months of kindergarten and declines sharply in subsequent years — related
• The positive relationship between kindergarten entrance age and achievement primarily reflects skill accumulation prior to kindergarten rather than heightened in-school learning ability — related
• The entrance-age achievement association is especially pronounced among children from upper-income families — related
• Kindergarten redshirting rates have remained around 5% of kindergarteners for roughly two decades — related
• At the end of first grade, children who repeated kindergarten had lower reading and math knowledge and skills than children who started on time — related