"I think if you stick to the routine around that time they know that it's time to go to bed," said Johnny Clarke, Jimmy's dad.
It makes good sense, but now new evidence shows preschool-aged children who have regular and consistent bedtimes scored higher in language, literacy and math skills than children whose parents report they did not have a routine bedtime.
"We know that getting proper sleep is not only important for mood and behavior and not being tired. But it helps the memory," said Dr. Christopher Tolcher, American Academy of Pediatrics. "We know that school aged children do better in school when they get proper sleep -- even in high school."
SRI International researchers interviewed 8,000 parents about their child's sleep and academic achievements.
Children who had routine early bedtimes took less time to fall asleep and had longer total sleep times than children who had inconsistent bedtimes.
The research also shows preschool-aged children should get the minimum of 11 hours of sleep every night. But, most kids don't.
Researchers say kids who got less than 11 hours had lower cognitive awareness, development skills and worse grades.
"Children need a certain amount of sleep like they need proper nutrition," said Dr. Tolcher. "Children should not be able to choose how much sleep they get. It's up to the parent to set that limit and enforce it consistently."
Experts suggest parents create a routine before bed, like a bath and reading a book. Dr. Tolcher says anything that is calming and relaxing should do the trick.