In this book, the author aims to identify how the process of training maths teachers is constituted in the state of Maranhão, with a focus on the municipality of Arari. The historical framework used is the implementation of the National Education Guidelines and Bases Law - LDBEN, Law No. 9.394/96. The research used the theoretical framework of Oral History as a qualitative research methodology. The oral narratives were based on interviews with teachers from the public school system in the municipality. The following procedures were adopted in the process of creating the oral sources: drawing up the interview script, conducting recorded interviews, transcribing and textualising the interviews and obtaining a letter of assignment. The script contained questions about the initial training of maths teachers, so as to enable them to revisit memories of their initial training. However, some changes were necessary as one of the teacher's answers prompted other questions. From the analysis of the narratives, the conditions of initial training and experiences in teaching stand out.