How Do Earlier School Times Affect Young Students?

A New Study Shows Lower Academic Performance for Elementary Students.

Posted Jun 17, 2014

Vigorous debates have been occurring in school districts across the U.S. regarding whether moving start times for school later in the morning will yield benefits for high school students’ academic performance and behavior. Proponents are relying on research and professional opinion (including my own) that suggests high school students may function better cognitively and emotionally at school when they don’t have to begin school so early – as early as 7:30 AM- or even earlier (e.g. for zero period) and consequently will be better able to get a good night’s sleep.  Opposition to change has been strong in some cases, and a few arguments against changing have been problems in bus scheduling, less time for afternoon sports practice, and belief that most high school students will simply stay up later and get no more sleep. In order to run two bus routes – one earlier and one later, most schools in the past have begun high schools earlier with middle and elementary schools beginning later.  Starting high schools later almost always means schools for younger children will have to begin earlier. In many cases, school boards have been appointing committees to weigh the pros and cons of changes. 

In a study published online today in the Journal of Educational Psychology, a team of researchers looked at the relations of differing school start times on academic achievement test scores in 718 elementary schools across the entire state of Kentucky. One  goal of the study was to determine if early school start time is especially associated with low academic performance in schools where a high number of students are from lower-income families.  I have proposed before (e.g. Buckhalt, 2011) that insufficient sleep may be part of the reason for the persistent achievement gap between children from lower and higher income children. Several results are notable:

1.  Around half of elementary schools (48.8%) began before 8:00AM and half (51.2%) began after8:00 AM. 

2. It was found that earlier start times were associated with lower scores, but only from schools with FEWER children who received free and reduced price lunches (a proxy for economic advantage/disadvantage). This finding was contrary to what was expected.

3. Schools with later start times also had more students who were “retained” – held back a grade.This was also an unexpected finding.

Among conclusions reached by the authors are:

1. While making school start times later for high school students may yield benefits, they may come at the risk of poorer performance for elementary school students.

2. Later school start times may not help in closing the achievement gap between students from higher and lower income families.  It may be that that poverty is associated with so many risk factors for low achievement that the single act of beginning school later is not enough to overcome the effects of multiple risks. In fact, the achievement gap may be exacerbated if students from high income families ARE helped significantly by later start times.

I have only provided a summary of some highlights from the study. Much more detail is provided in the article itself about how the study was framed in the context of past research, how the data were collected and analyzed, the results, and how the results were interpreted.

The press release from American Psychological Association:

Full article:

Full article citation:

Keller, P. S., Smith, O. A., Gilbert, L. R., Bi, S., Haak, E. A., & Buckhalt, J. A. (2014, June 16). Earlier School Start Times as a Risk Factor for Poor School Performance: An Examination of Public Elementary Schools in the Commonwealth of Kentucky. Journal of Educational Psychology. Advance online publication.