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How Early High School Start Times Can Lead to Absentee Students

This article was originally posted on NC State News.


Melinda Morrill |

Matt Shipman |

A new study finds that earlier high school start times can have significant adverse consequences for students, including increased rates of tardiness and absenteeism.

“The American Academy of Pediatrics recommends that high schools begin class after 8:30 a.m., but we know that most schools start much earlier,” says Melinda Morrill, an associate professor of economics at North Carolina State University and corresponding author of a paper on the work. “We were able to look at five high schools that moved start times from 8:05 a.m. to 7:25 a.m. in order to examine the effect that the change had on students.”

The researchers looked at data on seven cohorts of students, with graduation years ranging from 2013 to 2019. Specifically, researchers looked at data from the freshman, sophomore and junior years of each cohort. The change in start times was implemented in the 2012-13 school year. As an additional control group, the researchers also looked at data from 14 other high schools in the same school district that had already adopted a 7:25 a.m. start time.

“There’s a growing body of research that suggests earlier start times can hurt test scores,” Morrill says. “We looked at that, but the numbers weren’t statistically significant one way or the other.”

“However, the move to the earlier start times caused a small increase in the number of students who did not advance to 12th grade on time,” says John Westall, a Ph.D. candidate at NC State and co-author of the paper. “Specifically, the move from 8:05 to 7:25 was associated with students being 8% more likely not to advance to 12th grade on schedule.”

“We also wanted to look beyond testing to see if there were effects on other measures of academic engagement,” Morrill says. “And we found a significant increase in both absences and tardiness.”

“The change to an earlier start time led to an increase of about one additional absence per year and just over three additional tardy arrivals per year for students,” Westall says. “So students were definitely missing more school.”

“Looking at all 19 of the schools, we found that historically, the five schools that started at 8:05 had significantly lower rates of absenteeism and tardiness than the 14 schools that started at 7:25,” Morrill says. “But once those five schools moved their start time to 7:25, those advantages disappeared.

“The take-home message here is that we need to look at more than just test scores if we want to understand all of the ways that early start times can affect high school students,” Morrill says. “We know that school districts have to consider a wide range of issues, such as transportation logistics, student safety, extracurricular activities and school finances. But the more we look, the more the findings suggest that there are significant consequences of early start times for students.”

The paper, “High School Start Times and Student Achievement: Looking Beyond Test Scores,” is published in the journal Economics of Education Review. The paper was co-authored by Matthew Lenard, a graduate student at the Harvard Graduate School of Education.


Note to Editors: The study abstract follows.

“High School Start Times and Student Achievement: Looking Beyond Test Scores”

Authors: Matthew Lenard, Harvard University; Melinda Morrill and John Westall, North Carolina State University

Published: April 24, Economics of Education Review

DOI: 10.1016/j.econedurev.2020.101975

Abstract: The American Academy of Pediatrics recommends that U.S. secondary schools begin after 8:30 AM to better align with the circadian rhythms of adolescents. Yet due to economic and logistic considerations, the vast majority of high schools begin the school day considerably earlier. We leverage a quasi-natural experiment in which five comprehensive high schools in one of the nation’s largest school systems moved start times forty minutes earlier to better coordinate with earlier-start high schools. Here, disruption effects should exacerbate any harmful consequences. We report on the effect of earlier start times on a broad range of outcomes, including mandatory ACT test scores, absenteeism, on-time progress in high school, and college-going. While we fail to find evidence of harmful effects on test scores, we do see a rise in absenteeism and tardiness rates, as well as higher rates of dropping out of high school. These results suggest that the harmful effects of early start times may not be well captured by considering test scores alone.