Unschooling is a form of home education, which is the education of children at home rather than in a school. Home education is often considered synonymous with homeschooling. Unschooling contrasts with other forms of home education in that the student's education is not directed by a teacher and curriculum. Unschooling is a real-world implementation of "The Open Classroom" methods promoted in the late 1960s and early 1970s, without the school, classrooms or grades. Parents who unschool their children act as "facilitators," providing a range of resources, helping their children access, navigate, and make sense of the world, and aiding them in making and implementing goals and plans for both the distant and immediate future. Unschooling expands from children's natural curiosity as an extension of their interests, concerns, needs, goals, and plans.Homeschools use a wide variety of methods and materials. There are different paradigms, or educational philosophies, that families adopt including unit studies, Classical education (including Trivium, Quadrivium), Charlotte Mason education, Montessori method, Theory of multiple intelligences, Unschooling, Radical Unschooling, Waldorf education, School-at-home, A Thomas Jefferson Education, and many others. Some of these approaches, particularly unit studies, Montessori, and Waldorf, are also available in private or public school settings. It is not uncommon for the student to experience more than one approach as the family discovers what works best for them. Many families do choose an eclectic approach. For sources of curricula and books, "Homeschooling in the United States: 2003" found that 78 percent utilized "a public library"; 77 percent used "a homeschooling catalog, publisher, or individual specialist"; 68 percent used "retail bookstore or other store"; 60 percent used "an education publisher that was not affiliated with homeschooling." "Approximately half" used curriculum or books from "a homeschooling organization", 37 percent from a "church, synagogue or other religious institution" and 23 percent from "their local public school or district." 41 percent in 2003 utilized some sort of distance learning, approximately 20 percent by "television, video or radio"; 19 percent via "Internet, e-mail, or the World Wide Web"; and 15 percent t king a "correspondence course by mail designed specifically for homeschoolers." Individual governmental units, e. g. states and local districts, vary in official curriculum and attendance requirements. Unit studies The unit study approach incorporates several subjects, such as art, history, math, science, geography and other curriculum subjects, around the context of one topical theme, like water, animals, American slavery, or ancient Rome.[unreliable source?] For example, a unit study of Native Americans could combine age-appropriate lessons in: social studies, how different tribes lived prior to colonization vs. today; art, making patterns or artifacts influenced by Native American decorative crafts; history (of Native Americans in the U.S.); reading from a special reading list; and the science of plants used by Native Americans. Unit studies are particularly helpful for teaching multiple grade levels simultaneously, as the topic can easily be adjusted (i.e. from an 8th grader detailing and labeling a spider's anatomy to an elementary student drawing a picture of a spider on its web). As it is generally the case that in a given "homeschool" very few students are spread out among the grade levels, the unit study approach is an attractive option. All-in-one curricula All-in-one homeschooling curricula (variously known as "school-at-home", "The Traditional Approach", "school-in-a-box" or "The Structured Approach"), are methods of homeschooling in which the curriculum and homework of the student are similar or identical to what would be taught in a public or private school; as one example, the same textbooks used in conventional schools are often used. These are comprehensive packages that contain all of the needed books and materials for the whole year. These materials are based on the same subject-area expectations as publicly run schools which allows for easy transition back into the school system. These are among the more expensive options for homeschooling, but they require minimal preparation and are easy to use. Step-by-step instructions and extensive teaching guides are provided. Some include tests or access information for remote testing. Many of these programs allow students to obtain an accredited high school diploma.