This document discusses several research projects conducted in the Czech Republic related to collecting ethnic data in education. It outlines projects focused on analyzing the transition of Roma pupils from elementary to secondary school, monitoring the situation in Roma localities, and analyzing forms of segregation of socially disadvantaged children. The document also discusses definitions of Roma ethnicity, methods of self-reporting versus external classification, and factors teachers use to identify students as Roma such as appearance, name, family history, place of residence, and economic conditions.