Why We Sleep at Night

Your body has a clock inside it.

This clock lives in your brain and tells you when to sleep.

When the sun goes down, your body makes a special chemical.

This chemical makes you feel tired and ready for bed.

All night, your body repairs itself and your brain sorts new memories.

That is why sleep helps you learn better the next day.

In the morning, light comes through your eyes and tells your brain to wake up.

If you stay up late, your inner clock gets confused.

Then you may feel sleepy during the day.

Going to bed at the same time every night keeps your clock happy.