Using test data for all children attending Danish public schools between school years 2009/10 and 2012/13, we examine how the time of the test affects performance. Test time is determined by the weekly class schedule and computer availability at the school. We find that, for every hour later in the day, test performance decreases by 0.9% of an SD (95% CI, 0.7-1.0%). However, a 20-to 30-minute break improves average test performance by 1.7% of an SD (95% CI, 1.2-2.2%). These findings have two important policy implications: First, cognitive fatigue should be taken into consideration when deciding on the length of the school day and the frequency and duration of breaks throughout the day. Second, school accountability systems should control for the influence of external factors on test scores.cognitive fatigue | time of day | breaks | standardized tests | education

Using linked Danish survey and register data, we estimate the causal effect of age at kindergarten entry on mental health. Danish children are supposed to enter kindergarten in the calendar year in which they turn 6 years. In a "fuzzy" regression-discontinuity design based on this rule and exact dates of birth, we find that a 1-year delay in kindergarten entry dramatically reduces inattention/hyperactivity at age 7 (effect size = -0.73), a measure of self-regulation with strong negative links to student achievement. The effect is primarily identified for girls but persists at age 11.

Using Danish administrative data on all high school graduates from 1984 to 1992, I show that local unemployment has both a short-and a long-run e ect on school enrollment and completion. The short-run e ect causes students to advance their enrollment, and consequently their completion, of additional schooling. The long-run e ect causes students who would otherwise never have enrolled to enroll and complete schooling. The e ects are strongest for children of parents with no higher education.

In many developed countries, children now begin their formal schooling at an older age. However, a growing body of empirical studies provides little evidence that such schooling delays improve educational and economic outcomes. This study presents new evidence on whether school starting age influences student outcomes by relying on linked Danish survey and register data that include several distinct, widely used, and validated measures of mental health that are reported out-of-school among similarly aged children. We estimate the causal effects of delayed school enrollment using a "fuzzy" regression-discontinuity design based on exact dates of birth and the fact that, in Denmark, children typically enroll in school during the calendar year in which they turn six. We find that a one-year delay in the start of school dramatically reduces inattention/hyperactivity at age 7 (effect size = -0.7), a measure of self regulation with strong negative links to student achievement. We also find that this large and targeted effect persists at age 11. However, the estimated effects of school starting age on other mental-health constructs, which have weaker links to subsequent student achievement, are smaller and less persistent.

General rightsThis document is made available in accordance with publisher policies. Please cite only the published version using the reference above. Full terms of use are available: http://www.bristol.ac.uk/pure/about/ebr-terms Care around birth may impact child and mother health and parental health investments. We the years 2007-2009 in a differences-in-differences framework. We show that the strike reduced the 10 number of mothers' prenatal midwife consultations, their length of hospital stay at birth, and the 11 number of home visits by trained nurses after hospital discharge. We find that this reduction in care 12 around birth increased the number of child and mother general practitioner (GP) contacts in the 13 first month. As we do not find strong effects of strike exposure on infant and mother GP contacts 14 in the longer run, this result suggests that parents substitute one type of care for another. While we 15 lack power to identify the effects of care around birth on hospital readmissions and diagnoses, our 16 results for maternal health investments indicate that strike-exposed mothers-especially those who 17 lacked postnatal early home visits-are less likely to exclusively breastfeed their child at four months. 18Thus reduced care around birth may have persistent effects on treated children through its impact did not receive early home visits. Similarly, mothers who gave birth towards the end of the two-months 24 strike did not receive all regular midwife contacts, were discharged early, but received early home visits 25 after discharge (as the strike was finished by the time they were discharged). These observations justify 26 our identification strategy: We compare the differences in outcomes for children and mothers in a set of 27 periods defined relative to the 2008 strike, to the same differences in outcomes of mothers and children 28 in the same periods in 2009 (difference-in-differences framework). 29Children and mothers who were impacted by the strike have more general practitioner (GP) contacts 30 in the first month of the child's life. This increase in health care usage may indicate both, underlying 31 health problems of treated mothers and children and substitution of one health care service with another 32 in the setting of universal health insurance in Denmark (i.e., a setting were GP visits are free of charge.) 33Exploiting the variation in treatment intensity, we show that especially for children, this increase of 34 GP visits appears to be driven by a lack of early home visits by trained nurses, who usually monitor 35 2 children's health and advise parents on infant care. We find no strong persistent effects on longer-run 1 health care usage (GP contacts). Moreover, we find no effects on hospital readmissions or a set of relevant 2 diagnoses (child nutritional problems, postpartum maternal complications). Unfortunately, these results 3 are imprecise, likely due to power issues. Additionally, nurses managed to keep up a minimum level of 4 care, and we do not observe which women were e...