The ideas of a group of ninth grade Basic General Education students are analized. (14 – 15 years old). The mentioned ideas are related to nature and perception of colour. This was possible after having – the students – participated in didactic proposals that approached the referred theme, once they achieved the entrance to Second Cycle. These ideas are characterized according to underlying ontological, conceptual and epistemological principles, as well as in relation to reasoning schemes associated with them. The consistence and coherence of the responses given by these students to a multiple choice test, and a questionnaire containing open problems, are evaluated. Most of the students present ideas about colour coherent with science, being able to develop explanations that relate an important number of variables, properly.