Hello Florence.  This is such a timely topic - as you say, with a new school year aproaching if not already in motion!  It seems the only way parents will be able to help their kids with the sleep struggle is by enforcing a daily schedule that reduces "chat time" and increases "quiet time".  I know it seems kind of funny but it works with my little kids who fight me at nap time.

We have quiet time mostly every day after lunch.  The kids don't have to sleep but they do have to sit in their rooms on the beds/cribs and read or draw or pray.  No playing with polly pockets or stuffed animals or dolls.  Inevitably some of the three will fall asleep as they let their little bodies and minds unwind.

Sounds like maybe we should try this kind of thing with the older children and see if it works.  We just igh tbe surprised!

Take care and all the best, sue

ps - for more on teens and sleep check out these posts and articles.