on the popular consciousness". In 2006, Hirsch published The Knowledge Deficit, in which he continued the argument made in Cultural Literacy. Disappointing results on reading tests, Hirsch argued, can be traced back to a knowledge deficit that keeps students from making sense of what they read. In 2009, he published The Making of Americans: Democracy and Our Schools, in which he makes the case that the true mission of the schools is to prepare citizens for participation in our democracy by embracing a common-core, knowledge-rich curriculum as opposed to what Hirsch claims to be the current content-free approach. He laments 60 years without a curriculum in US schools because of the anti-curriculum approach championed by John Dewey and other Progressives. In 2016, he published "Why Knowledge Matters: Rescuing our Children from Failed Educational Theories", outlining the three major problems with education in the United States: the emphasis on teaching skills, such as critical thinking skills, rather than knowledge, individualism rather than communal learning, and developmentalism, that is, teaching children what is "appropriate" for their age. Core Knowledge Hirsch established the non-profit Core Knowledge Foundation and serves as its director. The Foundation began publishing its Core Knowledge Sequence in the 1990s. This includes eight books as part of the Core Knowledge Grader Series of books. The series begins What Your Preschooler Needs to Know and ends with What Your Sixth Grader Needs to Know. The series, which has been revised and updated over the years, have been particularly popular with parents who homeschool, as well as parents whose children attend Core Knowledge schools. In 2011 a British version of The Core Knowledge Sequence was published online. The books began to be adapted for the UK, beginning with What Your Year 1 Child Needs to Know. By 2015, there were about 1,260 schools in the US (across 46 states and District of Columbia) using all or part of the Core Knowledge Sequence. The Foundation believes that the actual number is much higher, but only counts schools that submit a "profile form" to the Foundation annually. The profile of Core Knowledge Schools in the US is diverse—including public, charter, private and parochial schools in urban, suburban and rural locations. Independent nonprofit GreatSchools.org reports that more than 400 of these schools are preschools. In his 2014 article published by Thomas B. Fordham Institute, Robert Pondiscio, the author of How the Other Half Learns in