This article presents a teaching intervention where programming was used to facilitate preschoolers' learning of mathematics, especially in their development of spatial thinking. In the intervention, the programming was made with a small programmable robot especially designed for young students. The results indicate that the children developed their ability to mentally compare and connect movements in reality with maps and symbols. Further, the children showed ability to mentally envision, hold in mind, and conceptualize actions and relationships between paper maps, gridded maps, and symbols. Thus, the intervention indicates potential in teaching mathematics through programming in preschool.