The kids are still used to sleeping late. They should have started changing their sleep pattern this week otherwise they will have difficulty waking up on time once school begins a week from now. They could listen to music on their cellphone all they want as long as their sleep will not get interrupted by the loud sound emanating from their wireless microphone headset.
They always reason out that they are big enough to know when to go to bed, but they need enough hours of sleep to get them alert in school. I just don’t know how to convince them to sleep early. Do you have any suggestions?