Giving teenagers a bit more of a lie-in on a school morning could have significant benefits for their mood and health. Researchers from the Hasbro Children's Hospital in Providence studied 201 children in Years 9 to 12 who all went to a private high school in Rhode Island. Over the course of the study the start of the school day was put back from eight until half past eight. After putting the start of the school day back the pupils said that they slept much better and were more motivated. Daytime sleepiness, fatigue and depressed mood were all reduced and class attendance improved. The percentage of students getting less than 7 hours sleep fell by 79.4% and those reporting at least 8 hours of sleep rose from 16.4% to 54.7%. Despite having reservations to start with both the students and the teachers voted overwhelmingly to continue with the later start. It is now thought that although teenagers sleep cycle changes so that they get up later and go to bed later they still need the same amount of sleep as children - about 9 1/4 hours a night.
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