With the start of a new school year comes the retooling of your child’s summer sleep routine. But just how much sleep are kids supposed to get? If you’ve found yourself asking this question, we’ve got the latest sleep guidelines for babies, kids, and teens— courtesy of CBS News by way of the American Academy of Pediatrics.

The academy’s report gave sleep guidelines for infants, toddlers, school age children, and teens. Here are the numbers:

Infants 4 to 12 months - 12 to 16 hours of sleep every 24 hours (including naps).

Children 1 to 2 years - 11 to 14 hours of sleep every 24 hours (including naps).

Children 3 to 5 years - 10 to 13 hours of sleep every 24 hours (including naps).

Children 6 to 12 years - 9 to 12 hours of sleep every 24 hours.

Teens 13 to 18 years - 8 to 10 hours of sleep every 24 hours.

Why the Numbers Matter

Getting the right amount of sleep is crucial to mental and physical health (and so is getting the right kind of sleep). For toddlers, it will cut down on fussy behavior and tantrums. For older kids, poor sleep health is linked to increased risk of injuries, obesity, diabetes, and depression, not to mention poor academic performance. With the ubiquity of smart phones, early school start times, and mountains of homework, teens, especially, are more sleep deprived than ever.

So engage in some daily physical activity, practice a little time management, and resist the temptation of that mesmerizing blue light at least 30 minutes before bedtime to begin reaping the benefits of better sleep health.