Want your preschooler to succeed? Make sure he gets…a nap.

If you want your preschooler to get a leg up on school, the best thing you can do may be to make sure he gets a nap after lunch.

That’s the finding of a study just released in the Proceedings of the National Academy of Sciences. Researchers studied 40 preschool-aged children, between 3-5 years, and found that they did a much better job on visual-spatial tasks when they slept for an hour after lunch—and the benefits even lasted until the next day!

What was particularly cool about it was that when they monitored the brain activity of the children, they found that there was more activity in the parts of the brain that are linked with learning and integrating new information. The children were literally using their naps to learn.

While apparently this is the first definitive research on the effects of naps on learning in preschoolers, it does seem a bit obvious that getting enough sleep is a good idea—especially if you want to retain information. Yet, many parents think of naptime as a waste of time;  time that could be better used for educational and other activities.

Overscheduling used to be just a problem of older children and adolescents—but increasingly, we are seeing overscheduled preschoolers.

Parents overschedule for all the best reasons. They figure that a longer school day means their child will learn more. They figure that starting sports and dance and other such things early not only means their children will get exercise, but get a head start on future success in those activities. Swimming lessons are a must, they think, for safety—and playdates and playgroups help with social skills (and give parents a chance to talk to another grownup).  All this, they figure, will help their children grow up to be successful adults.

But kids need to be, well, kids.  They need to nap—not just to rest, but because it’s crucial for helping the brain process new information. And just as much as they need to nap, they need to play; unstructured play is crucial for healthy development, mental health and, actually, academic success.

See, that’s the thing: we don’t need to turn childhood into prep school for adulthood. Childhood works pretty well when left alone. Think about the skills you really need to succeed as an adult. They are things like creativity, energy, perseverance, collaboration, intuition, imagination and optimism.  We can learn some of these things through activities and school, but children probably best learn them through unstructured, nurturing time with caregivers and friends—with rest breaks built in.

So, if you have a preschooler, as you work out your daily schedule, leave some time unscheduled—except for the hour or so after lunch. That should be naptime.