Schema mechanisms are software frameworks designed to reflect genetic and constructivist theories of cognitive development. Here we extend a schema mechanism by incorporating spatial information into sensorimotor schemas, and by embedding spatial processing capability in the mechanism, inspired by place cells and episodic memory in the mammals’ hippocampus. We report an experiment in which a mobile robot explores an open environment using only basic sensors: an ultrasonic telemeter and an inertial measurement unit. Results show that the robot constructs a reliable spatio-temporal graph of schemas and places, allowing the emergence of exploratory behaviors. These results contribute to our understanding of the spatio-temporal organization of behaviors in animals and suggest methods to create inexpensive robots capable of lifelike behaviors.