We live in a globalized society, traced by technological and industrial searches, where much is said about education and educational practices. However, some of these practices are still linked to traditionalism, where education is a means of trying to pass on to the student what he should learn, leaving aside his real needs, life perspectives, reflections and critical capacity, which affects the performance of his learning. In opposition to these facts, Ethnomathematics, a trend in Mathematics Education, comes to build an educational process based on the recognition of the mathematical knowledge developed in the daily practice of some coexisting cultures and to relate this knowledge to the teaching practice. The aim of this final work is to develop an anthropological research with an ethnomathematical approach found in the craft of the Naval Carpenters of the Vila do Itapuá - Vigia/PA, using their informal mathematics as a mathematical model to teach Geometry by means of a pedagogical intervention.