Considerable research has explored the impact of delayed school start times on students’ academic achievement and well-being. However, a recent study in The Journal of School Health goes beyond and investigates the effects of later school start times specifically on teachers’ health and daytime functioning.
The study took place in the Cherry Creek School District in Denver, Colorado, where new start times were implemented in the 2017-18 school year, and whose effects were documented in the Changing Start Times: Longitudinal Effects (CaSTLES) study. High schools started 70 minutes later (at 8:20), grades 6-8 started 40-60 minutes later (at 8:50), and elementary schools started 60 minutes earlier (at 8:00). Subjects were K-12 teachers teaching in each of the three study years, and who were surveyed on aspects of their sleep and performance at three points in the study: four months before the time change, and then six and eighteen months after the time change. An average of 1784 teachers responded each year, for an average 49.9% participation rate.
Results showed that high school teachers reported better sleep quality (a 65% increase at post-change) and increased alertness (a 51% increase at post-change), with no significant changes in either reported for elementary teachers.
Overall, the later start times for secondary schools and earlier start time for elementary schools yielded 85-90% of teachers reporting that they got enough sleep; the authors contrasted this with 64-74% of adults in Colorado reporting the same.
Source: Wahlstrom, K. L., Plog, A. E., McNally, J., & Meltzer, L. J. (2023). Impact of changing school start times on teacher sleep health and daytime functioning. The Journal of School Health, 93(2), 128–134. https://doi.org/10.1111/josh.13254