Lesson Study y Criterios de Idoneidad Didáctica en la Práctica Reflexiva de Profesores Ecuatorianos.

The reflective competence in mathematics instruction processes has gained strength in several research programs, making necessary the use of didactic tools that contribute to the assessment of the practice, regardless of the methodology used. In this line, the objective of this study is to determine the Didactic Suitability Criteria that emerge in the Lesson Study framework to strengthen instructional processes; Thus, a group of teachers of the second year of General Basic Education, who are participating in a professional training program in Ecuador, discuss and reflect on a process of instruction on numeration in an Lesson Study context, and through a content analysis, these discussions are reinterpreted, obtaining as a result that in the reflection of teachers, in the different stages of the Lesson Study, the six dimensions of the Didactic Suitability Criteria emerge.