Summer creates a break from routine. It’s not unusual for kids to sleep in and stay up late compared to the school year. Unless you have to wake your kids up for childcare before you go to work, it might not seem important to keep a regular bedtime. However, for young children and any child experiencing rapid growth, irregular sleep can adversely affect mood and behavior.

Researchers in the UK concluded that irregular bed times lead children between the ages of 3-7 to experience symptoms similar to jet lag.  Children who aren’t well-rested are more likely to be hyperactive, cranky, or socially inappropriate. Parents find this out themselves, but it is nice to have our experiences backed by research.

Interestingly, putting a child to bed at different times each night had more of an effect than going to bed late at the same time each night. Before the teen years, children experience increased melatonin levels as soon as natural light starts to fade, making the ideal bed time around 8pm. If your family’s schedule requires you to push it later than that, it’s best to stick with the same bed time each night, rather than trying to put the child to bed early sometimes and late the rest of the time.

Bedtime routines signal to your child that it’s time to settle in for the night. These signals occur at a neurological level: by turning off bright lights, electronics and screens, you assist the biological clock. (In fact, if you have trouble falling asleep at night, dimming the lights and turning the screens off 30 minutes before bed helps adults, too.)

For older children and teenagers, it’s difficult to enforce regular bedtimes. Teenagers naturally stay up late and sleep in. You might not be able to prevent this, but you can still set some rules to keep night owls safe and healthy. Establish curfews, set rules for Internet use, remind them that other people in the household need a full night’s sleep too, and consider encouraging them to get a summer job or internship that requires a regular wake-up time.