Peter Gray has studied how learning happens without any academic requirements at a democratic school. The Boston College research professor also wrote about the long history and benefits of age-mixed, self-directed education in his book Free to Learn. Over the years, as he encountered more and more families who had adopted this approach at home (these so-called “unschoolers” are estimated to represent about 10 percent of the more than two million homeschooled children), he began to wonder about its outcomes in that setting. Finding no academic studies that adequately answered his question, he decided to conduct his own.