The basic elements are provided to formulate and execute an educational research project from the critical-propositional approach, in which the diagnosis and solution of problems, in this case educational, are emphasized. The book is organized into four chapters, especially aimed at students in teacher training programs, who, although they have taken some preparatory courses in pedagogical research, do not have much practical experience in this area. The modular nature of this text allows each of its units to be taken independently of the others. They can be consulted separately and do not necessarily require prerequisites from other modular units. The teacher of the subject can combine them at her convenience, or insert other subjects that enrich the course.