Teenagers irritable because early school hours mess with their biological clocks

Scientists say there is no evidence to suggest early starts are beneficial

Kashmira Gander
Tuesday 30 September 2014 10:36 BST

Teenagers may not be irritable because of supposed attitude problems, but because early school hours affect their biological clocks, scientists claim.

New research shows that early starts can affect a teenager's mood, and changing when the school day begins can perk up a teen’s mood, benefit their health and enhance their ability to learn.

The team leading the study published in the journal ‘Learning, Media and Technology’ suggest that “our ability to function optimally [and learn], varies with biological time rather than conventional social times”.

Our sleep-wake cycle, or circadian rhythm, is the result of a complex balance between states of alertness and sleepiness regulated by a part of the brain called Suprachiasmatic Nucleus (SNC).

When a child’s biological time and school hours are closely aligned, like at the beginning of their school careers, their faculties are not affected.

But during adolescence, the consequences become drastically clear, when “‘the conflict between social and biological time is greater than at any point in our lives” according to the academics.

This is because during puberty, shifts in a teen’s bodyclock push the optimal time for sleep later into the evening, making it difficult for most teenagers to fall asleep before 11.00pm.

When early schools starts are coupled with a teen’s biological clock, the result is chronic sleep-deprivation, and low grades and health problems.

Academics added that there is there is a body of evidence showing the benefits of synchronising education times with teens’ body clocks. They go on to conclude that while studies "consistently" show adolescents benefit from waking later, there is no evidence to show that early starts have a positive impact on how healthy or how academically successful school students are.

Examples harnessing this body evidence include the United States Air Force Academy, where a later start policy saw the grades earned by a group of 18–19 year olds soar.

Join our commenting forum

Join thought-provoking conversations, follow other Independent readers and see their replies


Thank you for registering

Please refresh the page or navigate to another page on the site to be automatically logged inPlease refresh your browser to be logged in