The submitted article supports the multidisciplinary approach to STEM (Science, Technology, Engineer, Mathematics) teaching. Pupils in many countries are showing a reduced interest in STEM studies. Should we wish to increase their interest in STEM studies, then we must increase their interest in the study of mathematics. This article concentrates on providing an illustrative demonstration of the interdisciplinary relations between mathematics and information and communication technology (ICT) that can readily be used in teaching these two subjects at primary and secondary schools. The interdisciplinary teaching approach described promotes not only a better understanding of the study of mathematics but it also develops pupils’ logical reasoning and critical thinking. The need to interconnect mathematics and ICT in teaching is documented through specific examples. Attention is focused on number translation between individual numerical systems and entering numbers in the memories of computers and calculators.