By Dr. Marciene Mattleman

PHILADELPHIA (CBS) – Sleep is critical to brain development, memory function, and cognitive skills and discussions have been held for years about sleep-deprived teens – adolescents whose sleep cycles shift and have trouble falling asleep.

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Now, the Maryland-based Lloyd Society and Start School Later explored adolescents need for sleep and the consequences of appropriate start times for schools nationwide. With some schools starting at 7am, students don’t get the recommended 9 hours of sleep.

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In 2012, a study of 146 middle schoolers in Wake County, North Carolina was reported in Education Next, that found that pushing back start times an hour resulted in increased math and reading scores on standardized tests by 2-3 percentage points.

Challenges such as competitive sports practice and child care are considered in decision making but in Columbia, MO, Students Say, an advocacy group, successfully pushed start times from 7:30-9:00am.

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Read more in Education Week.