This research was conducted with the aim of finding out the effectiveness of the flipped class learning model in understanding mathematical concepts in class IV "Data" material in elementary schools. Based on existing phenomena, students still experience learning difficulties in elementary school mathematics lessons, especially in "Data" material. The research method used is the quasi-experimental method. The population taken was students in class IV of state elementary schools in Cimalaka and North Sumedang subdistricts, Sumedang Regency. The samples used were Sukamaju Elementary School as the experimental class and Karangpawulang Elementary School as the control class. The instrument used in this research is a test of the ability to understand mathematical concepts. The results obtained from three meetings were that mathematics learning could not be said to be effectively implemented using the flipped class learning model when compared with the conventional/lecture method.