I think one way to motivate kids to get more sleep at night would be to design a series of video games in which the monsters/creatures/aliens, etc., will automatically stop attacking your character between the hours of say 11:00pm - 7:00am.
At 11:00pm, they will cease fighting, will lay down and fall asleep. At 7:00am, they will wake up and resume attacking your character. If you attack them while they are sleeping, you will lose major points or you will instantly die.
Also, you will need to instruct your character to go to sleep during this same period, or your character will be very sleepy when the game resumes and will not perform well.
This particular time period would need to be hard coded into the game so it cannot be changed. So, at 11:00pm in New York City the enemies in the game will go to sleep, and the same thing happens in the game at 11:00pm in Los Angeles, and so forth in all the time zones around the world.
Would it be worth adding this feature to video games or would most kids just refuse to play them?