Ultraviolet index

The ultraviolet (UV) index is a number that tells us how strong the sun's rays are in your area. When you go outside and play in the sun, your skin gets very happy because it gets to soak up the sunlight and makes vitamin D which helps your bones grow strong. But, if you stay outside for too long, or if the sun is very strong, it can hurt your skin and eyes.

Scientists use a special tool to measure the strength of the sun's rays, which is called the UV index. The UV index is a scale from 0-11, where 0 means there are no sun rays, and 11 means the sun's rays are very strong and can hurt your skin and eyes in just a few minutes.

So, if the UV index is high, it means you need to be very careful when you go outside. Maybe you need to put on sunscreen or wear a hat and sunglasses to protect your skin and eyes. If the UV index is low, then you can play outside for longer without worrying about getting hurt by the sun's rays.

So, always check the UV index before you go outside to play in the sun, and remember to protect your skin and eyes from the sun's strong rays!