Here are some excerpts to take note of from the book Why We Sleep:
In Edina, Minnesota, school start times for teenagers were shifted from 7:25 a.m. to 8:30 a.m. More striking than the forty-three minutes of extra sleep that these teens reported getting was the change in academic performance, indexed using a standardized measure called the Scholastic Assessment Test, or SAT. In the year before this time change, the average verbal SAT scores of the top-performing students was a very respectable 605. The following year, after switching to an 8:30 a.m. start time, that score rose to an average 761 for the same top-tier bracket of students. Math SAT scores also improved, increasing from an average of 683 in the year prior to the time change to 739 in the year after. Add this all up, and you see that investing in delaying school start times—allowing students more sleep and better alignment with their unchangeable biological rhythms—returned a net SAT profit of 212 points....Numerous counties in several US states have shifted the start of schools to a later hour and their students experienced significantly higher grade point averages. Unsurprisingly, performance improvements were observed regardless of time of day; however, the most dramatic surges occurred in morning classes. It is clear that a tired, under-slept brain is little more than a leaky memory sieve, in no state to receive, absorb, or efficiently retain an education....Children from lower socioeconomic backgrounds are less likely to be taken to school in a car, in part because their parents often have jobs in the service industry demanding work start times at or before six a.m. Such children therefore rely on school buses for transit and must wake up earlier than those taken to school by their parents. As a result, those already disadvantaged children become even more so because they routinely obtain less sleep than children from more affluent families....Delayed school start times wonderfully increases class attendance, reduces behavioral and psychological problems, and decreases substance and alcohol use. In addition, later start times beneficially mean a later finish time. This protects many teens from the well-researched “danger window” between three and six p.m., when schools finish but before parents return home. This unsupervised, vulnerable time period is a recognized cause of involvement in crime and alcohol and substance abuse....School bus schedules and bus unions are a major roadblock thwarting appropriately later school start times, as is the established routine of getting the kids out the door early in the morning so that parents can start work early....ADHD symptoms are strongly overlap with those caused by a lack of sleep.... Adderall is amphetamine with certain salts mixed in, and Ritalin is a similar stimulant, called methylphenidate. Amphetamine and methylphenidate are two of the most powerful drugs we know of to prevent sleep and keep the brain of an adult (or a child, in this case) wide awake. That is the very last thing that such a child needs.... We estimate that more than 50 percent of all children with an ADHD diagnosis actually have a sleep disorder. (pp. 311-315)
Individuals who sleep fewer than seven hours a night on average cause a staggering fiscal cost to their country compared to employees who sleep more than eight hours each night. Inadequate sleep costs America and Japan $411 billion and $138 billion each year, respectively. The UK, Canada, and Germany follow. (p. 297)
