Children have little responsibility for their glasses. Their glasses frames are easy to get distorted. So the most durable and everlasting eyeglass frames are best for children. For example ,they can choose the pure titanium frames or bendable titanium frames.
When choosing glasses frames for children, thinner, lighter and stronger materials should be better for children because they are hard on their glasses. Stainless steel and titanium are best frames for children.
For children's eyeglasses frames, you should consider the Durability and Safety Issues. So it is better to choose unbreakable frame such as titanium frame. As for the style, because I don't know whether your children is boy or girl, you'd better take him to the store and let him/her choose what he/she likes.