Recent international education reports have highlighted some of the progress (as well as remaining disparity) in gendered education enrollment rates. But, the problem of gender segregation is still a very real issue even in some nations where girls are enrolled at levels on par with boys. Separate classes, curricula, and in many countries separate schools for boys and girls persist. This is juxtaposed against the opposite extreme that exists in some other countries' educational systems where girls are sometimes pushed into classes and advanced curricula for which they have not been adequately prepared. Using data from the most recent Trends in International Mathematics and Science Study (TIMSS) and the United Nations Educational, Scientific and Cultural Organization (UNESCO), this article reports on gender parity across approximately 45 nations in access (measured by enrollment rates), performance (mathematics achievement scores), and opportunity (implemented curriculum, teacher characteristics, classroom interaction) among 13-year-old girls and boys. The results of this study suggest that while cross-national gender parity numerically exists in many of these 45 nations in access, performance, and opportunity, the implications for gender equality are less clear. Several theoretical propositions are posited to explain these crossnational trends in gender parity versus equality.