America's sleepy children

NEW YORK (NBC News) - From the day babies are born parents shush, sing, rock and pretty much do whatever they can to get their kids to sleep. Despite good efforts a new poll finds it's not enough.

"If you compare what the parents are saying their child gets on average on school nights to what the recommendations are, it is off by about an hour," says Dr. Kristen Knutson of the National Sleep Foundation.

The foundation has released its annual "Sleep in America" poll of about 1,000 parents. The biggest sleep deterrents for kids are electronics in their bedrooms.

Three-quarters of elementary and middle school kids have at least one gadget glowing in what should be a dark room.

The percentage jumps to 90-percent of teens.

"Noise will disturb your sleep especially if it's left on. And also these really -- the more interactive devices, like video games or their tablets are mentally stimulating," Dr. Knutson explains.

The gadgets are here to stay, as is the need for sleep.

Experts say the way to keep both in harmony is to turn to another time-honored tradition: Good, solid parenting.

"We did find that parents who always enforce rules about how late their child can use these devices do have children that sleep more than parents who don't have these rules or don't enforce them regularly," Dr. Knutson says.

Parents may also want to power down to get a good night's sleep.

The poll found one in four parents admitted to texting or emailing after going to bed at least once in the past week.