The aim of this research was to describe teacher’s strategy in teaching mathematics on the topic of “exchanging money” to the first grade International Class Program’s students in SD Integral Luqman Al-Hakim Bojonegoro. The subject of this research was mathematics teacher and all students of I-A SD Integral Luqman Al-Hakim Bojonegoro. The data of this research was teacher’s strategy in teaching mathematics taken from the result of recording transcription of teaching and learning process through two observations. The data validity technique used in this study was member check, the process of data checking was taken by the researcher from the subject of the research to examine the possibilities of different assumptions. The result was that teachers described the topic of exchanging money to students through contextual teaching and learning by implementing contextual teaching and learning; where teachers used the market system on procedural knowledge, and used model on conceptual knowledge.