Want to help your kids start each day off right? Make sure they hit the pillow early enough each night.

Getting enough sleep benefits children in many ways. For starters, well-rested kids tend to behave better. They learn better too. And they may have fewer illnesses since sleep is good for the immune system.

For sleepy kids, it's a different story. Being drowsy can make kids crabby. It’s hard for them to concentrate on school work when they're tired. Worse, chronically sleepy kids may have a higher risk for some health problems, including obesity, high blood pressure, headaches and depression.

Even though sleep is essential, all too often children fall short. So it's important to make sure kids head off to bed early enough to get enough hours of nightly shut-eye. Experts say kids need this much sleep (including naps):

• Infants—12 to 16 hours.

• Toddlers—11 to 14 hours.

• Preschoolers—10 to 13 hours.

• Grade-schoolers—9 to 12 hours.

• Teens—8 to 10 hours.

These tips may help if your child has trouble falling asleep despite sticking to a bedtime:

Wind down. As bedtime approaches, keep noises to a minimum. Dim the lights. Darkness promotes melatonin (a sleep-inducing hormone).

Turn off the tech. Avoid letting kids watch or listen to upsetting or scary content within two hours of bed, and make sure they avoid TV, smartphone, tablet or other screens within an hour of their bedtime. Some content can be too stimulating. And the blue light from screens can interfere with the body's release of melatonin.

Start a relaxing routine. You might have your kids brush their teeth and read a book or take a warm bath before heading off to sleep.

Turn down the heat. It's easier to fall asleep in a bedroom that is a little bit on the cool side.

Watch the caffeine. Encourage your kids to limit or avoid caffeinated beverages four to six hours before bed.

Source: American Academy of Pediatrics