This study explored the relationship between educational technology and the mathematics achievement of South African and German students. Hierarchical Linear Models (HLM) showed that the availability of computers at school and using computers in the mathematics classroom in South Africa positively associated with the mathematics achievement of students. In Germany, the shared use of a computer/tablet with others at home and internet connection correlated positively with students’ mathematics performances while students who owned mobile phones achieved lower mathematics results than their counterparts. Similarly, in both countries, students owning a computer/tablet, students using computers/tablets “every or almost every day” for schoolwork at home, school and other places achieved lower mathematics results than their counterparts.