My teenager goes to bed at a decent hour, but has trouble falling asleep quickly and then has difficulty waking in the morning. Why?
The usual cause is a late or delayed sleep phase caused by late wakings on the weekend. The late weekend wakings become internalized, setting the biological clock on a late schedule, and leaving the child unready to fall asleep at an appropriate hour and unready to wake at the time necessary to go to school. The solution requires consistent wake-up times every day (weekday and weekend) as the bedtime gets adjusted to a regular time early enough to allow for sufficient sleep. This should be easy to accomplish until adolescence; then it may become more difficult partly for biological reasons and partly because of children’s desires to be more independent and to stay up very late on weekends as well as to sleep in whenever they can.