Robots are becoming an integral component of our society and robot-assisted learning has proved to be effective in promoting students’ interest and learning in STEM subjects. An underexplored area of robot-assisted learning is how the physically embodied nature of robots can be utilized to support learning through non-verbal communication, such as gesturing. In this paper, we discuss the design and development of a NAO robot that supports geometry reasoning with gestures. We evaluate two different ways for a robot to interact with college aged students (N = 30) while reasoning about geometric conjectures, and randomly assigned participants in two conditions. In the dynamic condition, the robot uses dynamic gestures that represent and manipulate geometric shapes in the conjectures.