“Read to your child daily” is printed on the bottom of every check-out receipt from our library. It’s a fitting slogan because reading books to kids matters. A 2010 article in the journal Research in Social Stratification and Mobility reported that children who grow up in homes with a lot of books get an average of three years more schooling than children from homes without books. This is independent of their parents’ education, occupation, and class. The results hold equally in rich and poor nations, in the past and in the present, and under Communism, Apartheid and capitalism. The data come from representative samples in 27 nations.