A lot of parents are concerned about the sleep habits of their teenagers.
Two general factors influence how sleepy or how alert anyone is at any given time during a 24 hour period, and teens are different on both counts.
The first factor is how long it's been seen you last slept. Teenagers need more sleep than adults, usually about 9 hours per night.
The second factor that influences the level of alertness and sleepiness is a biological rhythm called the circadian rhythm. In childhood, sleepiness develops around 8 or 9 o'clock at night. Teenagers have a shift in the circadian rhythm, and don't get sleepy till 10 or 11 pm.
Add in early school start times, social activities, and part time jobs, and it's no surprise that teens are among the sleepiest people in our society.
Falling asleep in class may cause problems, but dozing while driving can be deadly.
Remember, all of us function at our best after adequate rest.