This dissertation starts from the reading and interpretation of letters, because they have always fascinated me. The letter is an object that connects people, connects time, connects history and, moreover, somehow shapes the character of the people who write and read them. I want to learn how more than a personal letter about life, can a letter, each letter be an object that makes us grow in freedom, grow emotionally, learn. Knowledge is of infinite richness! Since time immemorial, letters have been written to one's father, grandmother, aunt, cousin and friend, who lived further or closer, this habit was still quite common even in the 1980s, when I started my relationship with writing and reading letters. Growing up and writing, the letters were completed with the freedom of drawings, cut-outs, collages, they were also small works of art. In this master's degree the pedagogical capacity of family letters is compared with letters from thinkers, writers, pedagogues, teachers and masters who left some of the most important letters ever published. I chose three letters from Nossa Junqueira, for analysis and comparison, as a sample of this family correspondence: a first letter (1897) from the father João da Camara, to his eldest son, Vicente; a second letter (1909) from another son, José Paulo to his mother Eugénia; and a third letter (1937) already at the end of the compiled correspondence, from this son José Paulo to his daughter, Maria da Assumpção. This presentation of private letters helps to foster the conviction that a colloquial, formal or narrative letter is pedagogical and should be used as such in the education system.