In order to explore students' interest towards S&T, we developed and validated a questionnaire that simultaneously takes into account 18 components (general interest in school-S&T, utility of school-S&T, teaching methods preferences, perceived importance and preference for school-S&T with respect to other school subjects, etc.). The questionnaire was administered to 1,882 students from grades 5 through 11 (seven grade levels). Findings indicate that: a) students show a high general interest in S&T and a preference for student-centred teaching methods rather than teacher-centred ones; however, few of them perceive the utility of school-S&T for everyday life, want to spend more time doing S&T in school or intend to pursue S&T related studies or careers. Grade level differences appear to be important while gender differences are weak; b) in terms of school subjects, perceived importance and preference order, S&T seem to occupy an intermediate position; the preference order is not, however, similar to the perceived importance order. The latter, and therefore the role of S&T in school, appear to be strongly influenced by its status or its social value given in the curriculum; c) the analysis based on correlations and regressions propose some important predictors of general interest towards S&T. The results highlight, among other things, the importance for school to intervene on certain factors that promote the development of students' interest in S&T. For instance, 1) to affirm the importance of S&T right from the beginning of elementary school, 2) to use teaching methods that allow students to establish links between what they learn in school and their lives, as well as methods centered on students' development of inquiry processes, 3) to promote cultural activities related to S&T, and 4) to promote a positive development of self-concept through quality schooling.