PHOTOCROMATIC LENSES: also known in the market with the Transitions name, but there are many other brands as well. These lenses change in color and light transmission depending on the intensity of the light exposure. Today there are many types of Transitions available depending on your child’s needs. You have the Transition Lenses which are clear indoors and at night, but when exposed to the outdoors they will darken depending on the amount of UV light present, this type of lenses will not darken inside the car. Then you have the Transition Vantage Lenses that have the same characteristics as the previous but they adapt to changing light, making them polarized when outdoors for the outdoor active kid these are a great option. The Transitions Xtractive Lenses activate behind the windshield of a car so these might be great for teens that are starting to drive. All Transitions no matter which one you select decrease glare reducing eye fatigue and block 100% UVA & UVB rays. Most come in two different colors brown or grey. 
POLARIZED LENSES: this type of lens protects eyes from reflections making them the better choice for all outdoor activities especially for water sports, fishing, boating and skiing.