Teenagers are going to have lessons on how to sleep. Materials to teach teenagers how to get enough sleep will be offered to schools across Scotland by the charity Sleep Scotland. The purpose is to help people realize the importance of sleep for young people's physical and emotional health . The charity Sleep Scotland said watching TV and using computers and mobile phones at night could stop teenagers from getting the nine hours of sleep they need. _ also offers a sleep advising service, saying getting enough sleep can improve grades and physical health. However, less sleep can result in being heavy and a greater risk of feeling worried and hopeless. The charity Sleep Scotland hopes to educate young people about why they need a full night's sleep and how to develop good sleeping habits. Most students find it very difficult to get up in the morning and pay attention to their study. Sleep is most surely a problem. Research shows that sleep time for teenagers around the world has got down in the past 10 to 20 years. A report by the charity Sleep Scotland said young people often believed they could make up for  sleep time during the week by sleeping late at weekends. However, by going to bed even later at weekends, they would actually have to experience a change in their body clocks, which would be harmful to their study on Monday mornings. According to the charity Sleep Scotland,  _  .
it's not important for teenagers to have enough sleep students can still pay attention to study easily without good sleeping habits it's helpful to sleep more at weekends less sleep may make teenagers heavy