Two thousand and twelve marked the fortieth anniversary of Title IX and the first Summer Olympic Games in which all attending nations sent female competitors. Too often, scholars of sport history conservatively frame the experiences of girls and women within a narrative of progress. College women's sport participation in particular is framed as a linear narrative beginning with the "new woman's" foray in college physical training, the non-competitive interwar coed, and the post Title IX female athlete. It is within this narrative that the college play day, a sport practice emerging in California and Washington in 1926 began to gain momentum as an additional form of extramural competition for college women. In this dissertation I interrogate which historical and societal forces contributed to the invention, diffusion, and evolution of the college play day. Though the play day is briefly included in descriptive narratives about women's physical activity and sport during the interwar era, deeper explorations are absent. This study aims to further elucidate the extent and variety of forms that the play day took. I aim to explore its general value within the college setting and its reception among women physical educators, colleagues, and play day participants. An additional research question I pose is what are the roles and contributions of certain individuals, alliances, and organizations involved in the invention, adoption, and evolutions of the college play day? Last, I question whether or not the play day is a site in which gender relations or other intersecting relations of power were reproduced, constructed, or transformed?