Dr. Kelley said that, when children are around ten, their natural wake-up time is about 6.30am; at 16, this rises to 8am; and, at 18, a person’s natural waking hour is 9am, although you may think they are just a lazy teenager. The normal school starting time works for 10-year-olds but not for 16- to 18-year-olds. For the older teenagers, it might be better to start the school day at 11am or even later. “A 7am wake-up time for older teenagers,” says Kelley, “is the same as a 4.30am start for a teacher in their 50s.”
Why does Kelley mention teachers in their 50s?
To explain how unnatural it is for teenagers to wake up at 7am To show how teachers are suffering due to the current school start time To argue that teenagers are lazy in comparison to their teachers To show that teachers agree with the observations Kelley makes