Sleep (mis)management, at one level, is obviously an individual issue, part of a larger energy-management challenge that also includes other forms of mental relaxation, such as mindfulness and meditation, as well as nutrition and physical activity. But in an increasingly hyperconnected world, in which many companies now expect their employees to be on call and to answer emails 24/7, this is also an important organizational topic that requires specific and urgent attention.

Source: The organizational cost of insufficient sleep | McKinsey & Company

I believe you can replace every instance of company and companies with school and schools and have a pretty good idea of why sleep is important. What’s even more important for education is the differences in teenagers and younger students and their sleep patterns.