School systems that track students into certain classes and academic programs based on ability end up worsening disparities between high and low performers, according to a far-ranging report that offers recommendations for improving education across Europe. The study, commissioned by a branch of the European Union (EU), also found that bilingual education has a positive effect on academic performance, and that non-native students benefit from being integrated within schools with majority native-born populations Titled "Explaining Student Performance," the study was conducted by the Danish Technological Institute, an independent research center. Its findings will be presented to members of the EU later this month in Brussels, Belgium. The report analyzes recent results from three major international studies of student academic skill: the Program for International Student Assessment, the Trends in International Science and Mathematics Study, and the Progress in International Reading and Literacy Study. The United States participates in all three studies.