Much of the research on mathematical games has focused on examining pre- and post-tests to determine childrens mathematical performance after they play games. This dissertation seeks to examine mathematical games using a different lens: by studying the process of playing math games through childrens participation and interactions. Using situated learning theories, which emphasize the social environment and a students participation in shaping what he or she learns, I studied what occurred during game play in order to better understand both mathematical and social issues. To explore these issues, I played a variety of math games with a group of four African-American first grade students from a rural county in the southern United States. We played math-related games for a total of 20 game sessions, each lasting, on average, 30 minutes.Organized as three article-length manuscripts, the dissertation begins with an article focused on methods of collecting data when children play math games in a classroom-like environment. It discusses the limitations of methods that have been used in the past and illustrates the use of methods that allow researchers to examine the process of game play rather than solely the end result. The goal is to provide insight about childrens participation and interactions so that researchers can anticipate and address issues that may arise when children play math games in a classroom environment. The second article examines childrens engagement with readily-available commercial and curricular math games when played as intended by the developers in a classroom-like environment. It examines issues that may arise when games are played without modifications. The third article examines the use of modified or differentiated games in order to meet the mathematical needs of all students in a class. The overarching goals of this dissertation are to find productive ways to bring games into the mathematics classroom and to support teacher educators work with pre-service and practicing teachers with regards to using games in the elementary mathematics classroom.