A 4-year longitudinal study investigating the relationship between flexible school starts and grades

Abstract

The mismatch between teenagers’ late sleep phase and early school start times results in acute and chronic sleep reductions. This is not only harmful for learning but may reduce career prospects and widen social inequalities. Delaying school start times has been shown to improve sleep at least short-term but whether this translates to better achievement is unresolved. Here, we studied whether 0.5–1.5 years of exposure to a flexible school start system, with the daily choice of an 8 AM or 8:50 AM-start, allowed secondary school students (n = 63–157, 14–21 years) to improve their quarterly school grades in a 4-year longitudinal pre-post design. We investigated whether sleep, changes in sleep or frequency of later starts predicted grade improvements. Mixed model regressions with 5111–16,724 official grades as outcomes did not indicate grade improvements in the flexible system per se or with observed sleep variables nor their changes—the covariates academic quarter, discipline and grade level had a greater effect in our sample. Importantly, our finding that intermittent sleep benefits did not translate into detectable grade changes does not preclude improvements in learning and cognition in our sample. However, it highlights that grades are likely suboptimal to evaluate timetabling interventions despite their importance for future success.

Later school start time is associated with longer school day sleep duration and less social jetlag among Norwegian high school students: Results from a large‐scale, cross‐sectional study

“…Furthermore, later school start times may not necessarily have subsequent effects on daytime functioning. Although several studies indicate that later school start time is related to increased school attendance and graduation rate, better cognitive functioning and improved mental health (McKeever & Clark, 2017; Neuroth et al, 2021; Vedaa et al, 2012), other studies have failed to show positive effects on school grades following delays in school start times (Biller, Molenda, Obster, et al, 2022; Thacher & Onyper, 2016). Unfortunately, it has proved difficult to conduct randomised controlled trials on the topic (Illingworth et al, 2019).…”

Actimetry-Derived 24 h Rest–Activity Rhythm Indices Applied to Predict MCTQ and PSQI

“…The most reliable and reproducible results have been obtained regarding the association of SJL with cognitive decline in students [4,5]. Researchers have found practical application in changing the working hours of educational institutions in order to increase the efficiency of the educational process: a one-hour delay in the start of classes [12,14,15] and a flexible school start time, taking into account the chronotype of students [13,16].…”