In this article we explore educators' use of Jean Piaget's theories concerning cognitive development to refute proposed social studies standards in Arizona. We describe the work of Piaget as well as the National Association for the Education of Young Children's developmentally appropriate practices as they apply to primary-grade children's capabilities of learning history. Recent research on children's ability to learn history, as well as research concerning the competing curricular frameworks of expanding communities and core knowledge, is described. During a public review of the proposed standards, educators and concerned citizens of Arizona were given opportunities to air their comments and concerns to the Arizona Department of Education. Our data consisted of written comments on the standards submitted by 50 public reviewers and copies of draft standards containing all proposed and accepted changes from the beginning of the public review period (March 1-25, 2005) until the Arizona Department of Education presented the standards to the state board of education for approval. During analysis of these comments, we found that teachers frequently referred to Piagetian theory and developmentally appropriate practices to refute the new standards. We concluded that children can learn history from either curricular framework as long as teachers employ practices that are developmentally appropriate. Unfortunately, as we explain, teachers' arguments, based on their understandings of Piaget, to refute content-laden curriculum in grades K-3 stifled substantive discussions that are at the heart of social studies education. (Contains 1 note and 1 table.)