Education is an ongoing confrontation between those who want to help children learn how to think, and those who want to teach them what to think. While there are numerous variations on these themes, the contrast can most clearly be found in the distinctions between child-centered Montessori systems, and teacher- and test-centered schools. Government schools usually fall into the latter category. Homeschooling, religious schools, un-schooling, and other forms tend to emphasize either the "how" or the "what" in their efforts with children.