Despite the growing body of integrationist literature on the study of language and on a wide range of language-related fields of inquiry, there is as yet no integrationist investigation of the field of language acquisition. This paper argues for the need of an integrationist study of what children learn about language and of how they learn it. What children come to know of language--its forms, content, and properties, its powers and its uses--is largely a culturally defined product of commonplace metadiscursive practices, in much the same way as what children come to know about other sociocultural, moral, and psychological domains is an outcome of their increasingly competent participation within the discursive practices of their developmental environment.