The literature has been consistent in highlighting the central role of mathematics during the early years. However, assessing mathematical learning in childhood represents a task that requires time and resources not always available in the early childhood classroom. This paper presents the development and results of the application of the Mathematical Thinking Test (TPM), an automated digital instrument based on games to measure early mathematical skills according to the Chilean curriculum. The results show good psychometric behavior of the instrument, which can be administered to large groups of childred in a quick and simple manner. These results allow us to conclude that the TPM is an efficient and effective solution to inform children's mathematical learning.