One reason teens might be temperamental? The vast majority are severely sleep deprived. A study conducted between 2007 and 2013 found that 95% of high school seniors report not getting even close to the recommended nine hours of sleep a night. Only 6 to 7% of females and 8 to 9% of males slept the proper amount, a finding the authors say calls for “universal interventions” with students. Those who don’t get enough sleep are more likely to do poorly academically and to be involved in a car crash. (The Week)