Abstract:In this paper we present a case study of a U.S. elementary school curriculum, Investigations in Number, Data, and Space , for the way it provides students with informal and formal algebraic experiences. We find that mathematical change is the unifying big idea of the algebra strand, and that other big ideas are patterns and relationships, representation, and modeling. We also find that its primary goals are aligned with two of the four NCTM algebra goals: Understand Patterns, Relations, and Functions and Analyze Change in Various Contexts. Finally, we find that its approach to achieving its goals is to foster mental processes that constitute the algebraic habit of thinking known as Building Rules to Represent Functions.