Abstract
The aim of this article is to present part of the results obtained by the intervention made from the author's Master degree project, which consisted in the development of a set of Astronomy classes for first year of High School students from a private school in the “Distrito Federal”, Brasilia, Brazil, making use of a didactical material called mini-planetarium (MP) as the main resource. Using Paulo Freire’s contextualization and dialogicity ideas as a theoretical framework guided by these lessons, it was proposed to the students the assembly and application of that resource in a planetarium session. During the project, some subjects such as the apparent trajectory of stars through Brasilia's sky, the location of the cardinal points beginning from the Southern Cross constellation, the color of stars and the stars being seen from a particular place were emphasized. It was found that the students showed an improvement of their understanding about these subjects, as well as a significant excitement with the developed methodology.