Research

Mixed

Adolescent sleep deprivation (less than 8.5 hours of weeknight sleep) and excessive daytime sleepiness are significantly associated with decreased academic performance (lower grades, tardiness) and reduced extracurricular activity participation.

If you are an adolescent or a parent of one, recognize that feeling sleepy in the morning is often biological, not just behavioral. Teens need roughly 8.5 hours of sleep. If school starts early, this is biologically difficult due to a natural shift in body clock (sleep phase delay). Prioritize sleep duration and consider later school start times as a structural solution to improve grades and mood, rather than just blaming the teen for 'poor sleep hygiene'.

GoodSupportsHIGH confidence
Seventy per cent of the students had less than 8.5 hours weeknight sleep... As ESS increased there was an increase in the proportion of students who felt their grades had dropped because of sleepiness, were late for school, were often extremely sleepy at school, and were involved in fewer extracurricular activities.
Edward S. Gibson et al. · BMC Public Health · 2006

Why this rating

Large sample size (n=3235), consistent results across two distinct surveys, and statistically significant associations, though limited by self-reported data.

Source

"Sleepiness" is serious in adolescence: Two surveys of 3235 Canadian students

Edward S. Gibson et al. · BMC Public Health · 2006

DOI 10.1186/1471-2458-6-116

cross_sectional · n=3235Cited 304×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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