This thesis explored the history of calculator usage in mathematics classrooms in the United States since 1975 with a focus on the attitudes of parents, educators, and national organizations. The influence of historical events, people, organizations, research, and trends was explored in depth. Studying the changes that calculators have brought to mathematics curriculum and how educators have reacted in the past will help to explain why math curriculum and school systems have adopted the attitudes and policies about calculators that they currently hold. This study found similar attitudes and reactions by parents and educators toward calculator usage in contrast to the opinions and mandates of organizations such as the NCTM, the College Board, and local school board administrations. Parents and educators were strikingly more hesitant and concerned regarding the effects of calculators than educational institutions. The results will be useful for future curriculum decisions in mathematics classrooms.