Children`s glass frames are either made of plastic or metal,

In the past, plastic eyeglasses were a better choice for children because they were considered more durable, less likely to be bent or broken, lighter in weight and less expensive. But now manufacturers are making metal frames . Metal composition varies, so ask the optician which one is best for your child, based on experience with different alloys. Ask for hypoallergenic materials if your child has shown sensitivity to certain substances. For example, some people are allergic to frame alloys that contain nickel.
So no matter plastic or metal are both of different advantages.