Start School Later movement

The Start School Later movement is a series of efforts by health care professionals, sleep scientists, educators, economists, legislators, parents, students, and other concerned citizens to restore a later start to the school day, based on a growing body of evidence that starting middle and high schools too early in the morning is unhealthy, counterproductive, and incompatible with adolescent sleep needs and patterns. During the second half of the 20th century, many public schools in the United States began shifting instructional time earlier than the more conventional bell time, thought to be about 9 a.m. Today it is common for American schools to begin the instructional day in the 7 a.m. hour and end about seven hours later, around 2 p.m. Most sleep research suggests that morning classes should begin no earlier than 8:30 a.m. for middle and high school students.

Advocates of a return to later school start times argue that sleep and school hours should be viewed as a public health issue, citing evidence linking early school start times to widespread sleep deprivation among teenagers as well as a wide array of acute and chronic physical, psychological, and educational problems. Not only do students consistently get significantly more sleep on school nights when their schools move to later start times, but later school hours have been consistently linked with improved school performance, reduced impulsiveness, and greater motivation, as well as with lower rates of depression, tardiness, truancy, and morning automobile accidents. Recent (2011) studies suggest that early school start times disproportionately hurt economically disadvantaged students and may even negatively impact future earning potential of students, offsetting any financial savings to the school system attributed to earlier hours.

In the early 1990s, the University of Minnesota's landmark School Start Time Study tracked high school students from two Minneapolis-area districts – Edina, a suburban district that changed its opening hour from 7:20 a.m. to 8:30 a.m. and the Minneapolis Public Schools, which changed their opening from 7:20 a.m. to 8:40 a.m. Many positive benefits to students were found, including:

A longitudinal follow-up study of the Minneapolis Public Schools after five years revealed that these and other positive benefits had persisted. In 2014, a three-year project using data from more than 9,000 students attending eight high schools in three states, found that when schools switched to a start time of 8:30 a.m. or later, attendance, standardized test scores and academic performance improved, and tardiness, substance abuse, symptoms of depression, consumption of caffeinated drinks, and the rate of traffic accidents involving teen drivers decreased.

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