In recent years, child development specialists have become increasingly concerned about how “screen time,” — where kids gaze at smartphones, tablets and TVs while the backlit screens cast glows on their youthful faces — is replacing time spent playing outside, where youngsters instead get their fill of a natural source of vitamin D thanks to the warmth and light from the sun. Outdoor learning environments, sometimes called “forest schools,” may be the answer to ensuring kids understand the importance of appreciating nature’s beauty and getting exposed to the elements. The first of these schools launched in Europe over five decades ago. Now, these learning options are springing up all over the world, including throughout the United States.