Science teaching by investigative methodology has been a didactic alternative for student learning. In this tool, the teacher can diversify his practice in everyday school life, aiming to streamline classes and develop skills and competences in students. Of the types of activities with an investigative character available, the investigative practice activity was chosen as the object of research in this study. To this end, an investigative activity on blood typing within the ABO system was developed, where students were able to simulate in a simple and safe way the reactions that occur during the procedure of identifying the blood group of the ABO system.