Background

A study was conducted in sleep research centers in Providence, Rhode Island; to determine the effects of a later school start time.  At this boarding school the schedule was altered, with a later start time, changing from 8:00 to 8:25.  The effects of this study were seen in the changes in the proportion of students who took naps, fell asleep during class, were tardy to class, were too tired to complete their studies, were too tired to socialize, and were too tired to participate in athletic events.  When classes commenced at 8:00, 25% of students were late to class at least once a week.  However when the school start time was changed to 8:25, the proportion of students late to class at least once a week fell to 16%.  This study used a chi-square homogeneity test to determine whether the proportions of each category changed from one start time to the next.  Their X²=5.69 and their p-value was 0.0171, so at the 0.05 level of significance they were able to reject their null hypothesis, concluding that the proportion of students late to class at least once a week significantly differed from one start time to the other.  For this study, 1,052 students were surveyed, and they were testing that a later start time would decrease daytime sleepiness and increase sleep duration.  Paired t-tests were also used to compare the differences in health related outcomes of students.  The purpose of the study was to determine whether a later start time increased sleep duration, therefore decreasing negative health issues, such as depression, sleepiness, and caffeine consumption. 

            Early school start times are a debated issue among many educators because many feel these lead to increased depression, unhealthy habits, and sleepiness that can affect grades and overall function.    A study was conducted in Minneapolis high schools where the school start time was changed from 7:15 to 8:40.  Another study was conducted in Edina where start times were changed from 7:25 to 8:30.  This second study was carried out because both cities varied based on race and economic variability, so that the results would be more valid.  The results in both of these studies despite diverse conditions resulted in a more alert and productive student body.  As well, tardiness decreased, attendance increased, and overall grades improved.  In a study published in Archives of Pediatric & Adolescent Medicine, the effects of a later start time from 8:00 to 8:30 were studied at a private New England high school.  Not only were student attitudes improved but teachers recorded a decrease in tardiness by 45%. 

            In a study conducted by the University of Minnesota, eight public high schools in 5 different districts in Minnesota, Colorado, and Wyoming, the grades earned, attendance, tardiness, and standardized test scores were recorded based on a start time change from 7:35 to 8:55.  In over half of the schools included in the study, the difference in mean tardiness between the two start times was proved to be a statistically significant decrease. When the start time was changed from 7:35 to 8:55, the proportion of students who slept for 8 hours or more increased from 44.2% to 66.2%.  This suggests that a later start time allows more students to get more sleep each night.  Overall, most studies show that a later school start time has a positive effect on tardiness, bringing the rates down, and a positive impact on overall student attitude and performance.  

WORKS CITED

http://www.gwern.net/docs/melatonin/2014-boergers.pdf

http://articles.latimes.com/2010/aug/23/health/la-he-school-time-20100823

http://conservancy.umn.edu/bitstream/11299/162769/1/Impact%20of%20Later%20Start%20Time%20Final%20Report.pdf