What Are the Effects of School Start Time on Student Achievement?

The Reference Desk receives several questions each month on school schedules. This week’s question focuses on one aspect of scheduling—school start times. Our researchers found that much of the research on school start times is linked to research on the sleep needs of children and adolescents.

Question

What does the research say about later school start times and student achievement?

Research Synthesis

Reference Desk researchers found resources that suggest school start times may have an impact on student achievement. A literature review of school start time and academic achievement found: “1) American adolescents are not having adequate sleep time; 2) insufficient sleep time could impair adolescents’ learning and development; 3) insufficient sleep can be ameliorated but not fully addressed by delaying school start time; but 4) it is not clear whether student academic achievement will improve along with a later school schedule; lastly, 5) insufficient sleep might not be as grave as what the media and some studies have depicted” (Yan, 2006; see resource below).

Publicly Available Resources

School Start Time and Academic Achievement: A Literature Review. August 2006; Yan, B. & Slage, M.; Overland Park, KS: Blue Valley School District; ERIC Document #ED493187; 19 pages.
From the abstract: “This study intends to strengthen our understanding of the relationship between school start time and student achievement by synthesizing findings from both medical and educational research. The review of the past research suggests that 1) American adolescents are not having adequate sleep time; 2) insufficient sleep time could impair adolescents’ learning and development; 3) insufficient sleep can be ameliorated but not fully addressed by delaying school start time; but 4) it is not clear whether student academic achievement will improve along with a later school schedule; lastly, 5) insufficient sleep might not be as grave as what the media and some studies have depicted” (p. 2).
Changing Times: Findings From the First Longitudinal Study of Later High School Start Times. December 2002; Wahlstrom, K.; NASSP Bulletin, Vol. 86, No. 633; pp. 3–21.
“This article presents findings from a 4–year study in a large, urban school district that altered high school start times significantly from 7:15 a.m. to 8:40 a.m.” (p. 1). Although the researchers had difficulty obtaining “clean” achievement data, “the comparison of students’ letter grades for 3 years prior to the change (starting time of 7:15 a.m.) and 3 years after revealed a slight improvement in grades earned overall, but the differences were not statistically significant” (p. 11). “[A]ttendance rates for all students in grades 9, 10 and 11 improved in the years from 1995–2000, with the greatest rate of improvement for grade 9 students” (p. 18). See also the study’s executive summary: Minneapolis Public Schools Start Time Study.
The Impact of School Daily Schedule on Adolescent Sleep. June 2005; Hansen, M., Janssen, I., Schiff, A., Zee, P. C., & Dubocovich, M. L.; Pediatrics, Vol. 115, No. 6; pp. 1555–1561.
“The results of this study demonstrated that current high school start times contribute to sleep deprivation among adolescents. Consistent with a delay in circadian sleep phase, students performed better later in the day than in the early morning. However, exposure to bright light in the morning did not change the sleep/wake cycle or improve daytime performance during weekdays. Both short-term and long-term strategies that address the epidemic of sleep deprivation among adolescents will be necessary to improve health and maximize school performance” (p. 1555).
Sleep: The E-ZZZ Intervention. December 2009; Bergin, C. A., & Bergin, D. A.; Educational Leadership, Vol. 67, No. 4; ERIC Document #EJ868289; pp. 44–47.

From the ERIC abstract: “Research has shown that students who do not get enough sleep are more likely to misbehave in school and have lower academic achievement than their peers with healthy sleeping habits. In this article, [the authors] share research into students’ sleep habits and conclude that helping students get adequate sleep has potential to raise academic achievement. They encourage teachers to talk with parents when students show signs of sleep deprivation. They also recommend that school eliminate late-night activities, ensure that homework does not require students to stay up late, and consider changing their start time.”

The Reference Desk also found these organizations and resources to be helpful in learning more about the sleep needs of adolescents in general:

National Sleep Foundation
From the website: “The National Sleep Foundation is a 501(c)3 charitable, educational, and scientific not-for-profit organization dedicated to improving sleep health and safety through education, public awareness, and advocacy.” The website’s ‘Hot Topics’ page includes an article on sleep deprivation in teens titled Backgrounder: Later School Start Times.
Sleep for Science

The Sleep for Science Research Lab provides a section on their website with resources focused on School Start Time.

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