This paper presents the process of design and validation of a rubric for measuring the teaching competence in classes of motor games and body language with preschool children. This implementation was carried out in the context of 'Fundamentals of corporal expression: motor games in Infant Education'--a subject located in the second academic year of the preservice teachers degree o fUniversity Jaume I of Castellón, Spain. The results obtained from the empirical analysis of the data show the validity and reliability of the rubric created, highlighting a result of 0,908 in the Cronbach's alpha and, in consequence, a very similar structure to the first model. In summary, from the theoretical justification presented and taking into account the results obtained, we offer a tool capable of measuring competence in teaching sessions of motor games and body language. We also would like to highlight the value of the process in itself, as an example for the development of new rubrics in the field of Didactics of Physical Education.